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ANATOMY  AND  PHYSIOLOGY 

FOR  NURSES 

B  U  N  D  Y 


TEXT-BOOK 


OF 


ANATOMY  AND  PHYSIOLOGY 

FOR   NURSES 


BY 

ELIZABETH  R.  BUNDY,  M.  D. 

MEMBER   OP  THE   MEDICAL  STAFF    OP  THE   WOMAN's  HOSPITAL  OF    PHILADELPHIA;    GYNECOLOGIST 

NEW  JERSEY    TRAINING    SCHOOL,   VINELAND;   FORMERLY    ADJUNCT    PROFESSOR   OF 

ANATOMY,  AND  DEMONSTRATOR    OF    ANATOMY   IN   THE  WOMAN's    MEDICAL 

COLLEGE     OF     PENNSYLVANIA;     FORMERLY     SUPERINTENDENT 

OF   CONNECTICUT  TRAINING   SCHOOL  FOR   NURSES 

NEW   HAVEN,  ETC. 


SECOND  EDITION 
REVISED  AND  ENLARGED 


WITH  A  GLOSSARY  AND  215   ILLUSTRATIONS 
42    OF    WHICH    ARE    PRINTED     IN    COLORS 


PHILADELPHIA 

P.   BLAKISTON'S   SON   &   CO 

1012   WALNUT  STREET 
1913 


PREFACE  AND  DEDICATION  TO  FIRST  EDITION. 


The  pupil-nurse  in  a  training-school  has  very  few  hours  at  com- 
mand for  the  study  of  text-books,  but  it  is  hoped  that  she  may 
find  in  this  "Anatomy  for  Nurses"  an  aid  to  the  acquirement  of 
that  knowledge  of  the  human  body  which  is  essential  to  the  full 
understanding  of  her  important  duties. 

In  preparing  a  book  of  this  kind,  the  inevitable  difficulty  of 
selection,  when  dealing  with  a  subject  of  such  magnitude,  is  at  once 
manifest.  What  appears  from  one  point  of  view  to  be  of  minor 
interest,  is  from  another  paramount  in  importance;  while  in  truth,  no 
detail  is  of  itself  insignificant. 

The  author  trusts  that  in  the  present  work  such  matters  as  are 
not  available  for  immediate  use  in  the  hospital  ward  may  still  be  of 
value,  to  meet  the  growing  need  of  the  graduate-nurse  as  she  finds 
herself  developing  with  the  practice  of  her  profession.  It  was,  in 
part,  to  meet  this  frequently  expressed  need  that  the  work  was 
undertaken. 

The  old  plan  of  systematic  anatomy  is  followed,  but  the  usual 
order  of  subjects  is  not  strictly  observed.  For  example,  the  descrip- 
tion of  the  blood-vessels  is  deferred  until  the  student  shall  have 
become  familiar  with  many  of  the  organs  from  which  a  large  number 
of  vessels  derive  their  names. 

The  chapter  entitled  "Foods  and  Digestion"  is  introduced  in 
response  to  a  request. 

Concerning  the  use  of  anatomic  terms,  indications  point  to  the 
general  adoption  of  the  nomenclature  accepted  by  the  German 
Anatomical  Society  at  the  meeting  of  1895,  ^^  Basle,  Switzerland. 
The  B.  N.  A.,  as  it  is  called,  will  soon  be  in  use  among  the  younger 
physicians  at  least;  therefore,  many  of  the  terms  belonging  to  it  are 
here  introduced,  and  several  tables  are  given  which  include  names 
not  found  in  the  text. 

The  author  gratefully  acknowledges  her  indebtedness  to  Dr. 
Marie  L.  Bauer  for  valuable  aid  in  the  preparation  of  the  book, 

vii 


Vlll  PREFACE   AND    DEDICATION    TO    FIRST    EDITION. 

and  to  Drs.  Frances  C.  Van  Gasken  and  J.  William  McConnell 
for  assistance  in  the  reading  of  proofs  and  for  helpful  suggestions. 

The  original  illustrations,  most  of  which  are  printed  in  colors,  are 
drawn  by  Chas.  F.  Bauer. 

To  the  members  of  the  nursing  profession,  with  cherished  recol- 
lections of  labors  and  responsibilities  shared,  this  Text-book  of 
Anatomy  is  dedicated. 

Elizabeth  R.  Bundy. 


CONTENTS 


INTRODUCTORY. 

Page. 
Plan  of  study,  anatomic  terms;  muscle,  nerve,  and  connective  tissues;  epithelial 
tissues;  serous  and  mucous  membranes;   processes  included   in  metabolism 
of  the  body i 

CHAPTER  I. 
BONE  TISSUE  AND  BONE  CLASSIFICATION.    ARTICULATIONS. 

Chemical  composition  of  bone;  structure  of  osseous  tissue;  marrow;  medullary 
and  nutrient  canals;  shapes  and  surfaces;  periosteum;  ossification;  divisions 
of  the  skeleton;  joint  movements;  remarks 8 

CHAPTER  II. 
BONES  AND  ARTICULATIONS  OF  THE  SKULL. 

Bones  of  the  cranium;  sutures  and  fontanelles;  bones  of  the  face;  the  mandibular 
joint;  the  skull  as  a  whole;  four  larger  fossae  of  the  skull;  the  teeth;  dentition; 
care  of  the  teeth;  clinical  and  obstetric  notes i6 

CHAPTER  III. 
BONES  AND  ARTICULATIONS  OF  THE  SPINAL  COLUMN  AND  TRUNK 

The  vertebra;;  Hgamenta  flava;  ligamentum  nucha;  movements  of  spinal  column; 
spinal  curves;  bones  and  articulations  of  the  thorax;  the  pelvic  girdle;  sacra- 
sciatic  ligaments;  dorsal  and  ventral,  or  neural  and  visceral  cavities;  clinical 
and  obstetric  notes 35 

CliAPTER  IV. 
BONES  AND  ARTICULATIONS  OF  THE  EXTREMITIES. 

Bones  of  the  upper  extremity;  pronation  and  supination;  bones  of  the  lower 
extremity;  patella;  Y-ligament,  crucial  ligaments;  arches  of  the  foot;  com- 
parison of  extremities;  articular  nerves;  clinical  and  surgical  notes;  special  notes     50 

CHAPTER  V. 
COMPLETION,    REPAIR  AND  PHYSIOLOGY  OF  BONES. 

Completion  of  long  bones;  the  skeleton  at  different  ages;  bones  in  infancy;  green- 
stick  fracture;  rachitis;  spina  bifida;   process  of  repair;  functions  of  bone 

tissues;  surgical  and  special  notes 70 

ix 


X  CONTENTS 

CHAPTER   VI. 

THE  CONNECTIVE  TISSUE  FRAMEWORK  AND  SKELETAL  MUSCLE 

SYSTEM. 

Page. 
Fascia,  deep  and  superficial;  inguinal  ligament;  bursae;  structure  of  muscles;  tendon 
and  aponeurosis;  origin  and  insertion;  muscles  of  expression,  of  neck  and 
thorax;  abdominal  muscles  and  linea  alba;  sheath  of  rectus,  semilunar  and 
transverse  lines.     Diaphxagm.;  surgical  a.nd  clinical  notes;  special  points  ...     75 

CHAPTER  VII. 

MUSCLES  OF  THE  EXTREMITIES. 

Structure  and  action  of  muscles  of  upper  extremity;  axillary  space;  pronators  and 
supinators;  vaginal  synovial  membranes;  annular  ligaments;  palmar  fascia; 
muscles  of  lower  extremity;  popliteal  space;  annular  ligaments;  Physi- 
ology of  muscle  tissue;  muscle  tissue  a  source  of  heat  and  electricity; 
tetanus;  cramp;  fatigue;  clinical  notes;  special  points;  classification  by  actions  .     94 

CHAPTER  VIII. 
THE  ORGANS  OF  DIGESTION. 

Alimentary  tract  or  canal;  glands  of  digestive  apparatus;  enzymes;  saliva,  alkaline; 
the  stomach;  gastric  juice,  acid;  the  intestine;  intestinal  fluids,  alkaline; 
viUi;  ileo-colic  valve;  cecum  and  appendix;  rectum  and  anal  sphincters; 
peristalsis;  liver  and  gall  bladder;  bile;  the  porta;  notes,  clinical  and  surgical  .   12a 

CHAPTER  DC. 
FOODS  AND  DIGESTION. 

Four  classes  of  foods  in  dietary;  air  as  food;  food  combination;  reasons  for  cooking 
food;  Digestion,  mechanical  and  chemical;  mastication,  insalivation ;  gastric 
digestion  (acid),  chyme;  intestinal  digestion  chyle;  peristalsis;  absorption; 
clinical  notes 141 

CHAPTER  X. 
THE  BLOOD  AND  CIRCULATORY  ORGANS. 

Blood-corpuscles  or  cells.  Erythrocytes  and  leucocytes;  ameboid  n;ovements, 
diapedesis;.  plasma  (alkaline);  normal  saline  solution;  coagulation;  arteries, 
capillaries;  veins;  the  heart;  chambers  and  valves  of  heart;  endocardium; 
systole  and  diastole;  the  pulse;  pericardium;  course  of  blood  through  the 
heart;  surgical  and  clinical  notes;  important  notes       152 

CHAPTER  XI. 
THE  CIRCULATION  AND  PHYSIOLOGY  OF  THE  BLOOD. 

Pulmonary  vessels;  aorta  and  branches;  arteries  of  the  head,  of  the  upper  extremity; 
palmar  arches;  thoracic,  abdominal  and  pelvic  arteries;  arteries  of  the  lower 
extremity;  veins,  deep  and  superficial;  jugular  veins;  azygos  veins;  superior 
vena  cava;  inferior  vena  cava;  portal  circulation;  fetal  circulation;  Physiology 
of  blood;  phagocytes;  opsonic  index;  collateral  circulation;  clinical  and 
surgical  notes j5y 


CONTENTS  XI 

CHAPTER  XII. 
THE  LYMPHATIC  SYSTEM. 

Page, 
Lymph  spaces,  capillaries  and  vessels;  lymph,  origin;  lymph  glands  or  nodes; 
edema,  effusion;  thoracic  duct;  right  lymphatic  duct;  principal  nodes;  the 
lymph  stream;  metastasis;  summary  of  functions;  c/jwica/ Mo/ej 194 

CHAPTER  XIII. 

THE  RESPIRATORY  ORGANS  AND  RESPIRATION. 

The  respiratory  tract;  the  nose,  nares  and  choanse;  the  larynx;  trachea,  bronchi  and 
bronchial  tubes;  ciliated  epithelium;  air  cells;  the  lungs;  the  pleura;  respiratory 
movements;  respiration  and  heat  production;  modifications  of  breathing; 
clinical  notes 202 

CHAPTER  XIV. 

THE  KIDNEYS.     THE  SKIN.     ELIMINATION. 

Structure  of  the  kidney;  the  ureter;  composition  of  urine;  suppression  of  urine; 
retention  of  urine;  structure  of  the  skin;  elasticity;  glands;  hair  and  nails; 
composition  of  perspiration;  regulation  of  body  temperature;  clinical  notes     .   211 

CH.\PTER  XV. 

MAMMARY  GLANDS.  DUCTLESS  GLANDS.  GENERAL  METABOLISM. 

Structure  of  mammary  gland;  milk;  colostrum;  mammary  abscess;  ductless  glands 
and  internal  secretion;  the  spleen,  structure  and  blood  supply;  leukemia;  the 
pancreas,  structure  and  blood  supply;  adrenals,  adrenalin;  thyroid  body; 
cretinism;  thymus  body  an  infantile  structure;  secretion  and  secreting  organs; 
excretion  and  excreting  organs;  animal  heat,  variations  and  regulation  of 
tempeTa.tuie;  clinical  and  practical  notes 219 

CHAPTER  XVI. 

THE  NERVE  SYSTEM. 

Two  divisions  of  the  nerve  system;  the  neuron,  cell  body  and  nerve  fiber;  cerebro- 
spinal division;  gray  and  white  nerve  tissues;  nerve  centers;  spinal  cord  and 
membranes;  structure  of  spinal  nerves;  5Mr^Jca/ and  c/zwfca/ Mo/es 229 

CHAPTER  XVII. 

THE  SPINAL  NERVES. 

Anterior  and  posterior  divisions;  the  cauda  equina;  cervical  plexus,  phrenic  nerve; 
brachial  plexus,  radial,  ulnar  and  median  nerves;  lumbar  plexus,  femoral 
nerve;  sacral  plexus,  sciatic  nerve;  Physiology  of  spinal  cord  and  sjiinal 
nerves;  reflex  action;  co-ordination;  electrical  stimulus;  points  0/  interest     .    .  235 


XU  CONTENTS 

CHAPTER  XVIII. 

THE  BRAIN  AND  CRANIAL  NERVES. 

Page. 
Structure  of  brain,  cortex  and  fibers;  fissures;  ganglia;  internal  capsule;  cerebellum; 
medulla  oblongata;  pons;  crura;  ventricles  of  brain;  membranes  of  brain; 
cranial  nerves;  Physiology  of  brain  and  cranial  nerves;  cerebral  localization , 
surgical  and  clinical  notes 249 

CHAPTER  XIX. 
THE  SYMPATHETIC  DIVISION  OF  THE  NERVE  SYSTEM. 

Vertebral  ganglia;  cardiac  and  splanchnic  nerves;  cardiac  and  celiac  (solar) 
plexuses;  semilunar  ganglia;  functions  of  sympathetic  nerves;  vasomotor 
and  reflex,  presiding  over  visceral  action;  Physiology  of  nerve  system  as  a 
whole;  important  notes       262 

CHAPTER  XX. 
THE  SPECIAL  SENSES  AND  THE  VOICE. 

General  and  special  sensation;  the  sense  of  smell,  olfactory  region;  the  sense  of 
touch,  touch  corpuscles;  the  sense  of  taste,  taste  buds;  the  sense  of  hearing, 
external  ear  and  auditory  canal;  middle  ear  or  tympanum  and  auditory  tube; 
internal  ear  or  labyrinth;  the  sense  of  sight;  structure  of  eyeball;  lacrimal  gland; 
the  voice;  organs  of  the  voice;  organs  of  speech;  vocal  glands;  clinical  notes  .   270 

CHAPTER  XXI. 
THE  PELVIC  ORGANS. 

The  rectum;  bladder;  urethra;  urethral  caruncle;  the  prostate  gland;  the  uterus; 
uterine  or  Fallopian  tubes;  the  ovaries,  ovulation;  corpus  luteum;  menstrua- 
tion; the  menopause;  the  vagina  and  infra-vaginal  portion  of  cervix  uteri; 
the  pudendum;  the  perineum;  the  testes  and  spermatic  cord;  clinical  and 
surgical  notes ^  .    .    .    , 283 

CHAPTER  XXII. 
A  BRIEF  STUDY  OF  IMPORTANT  REGIONS. 

The  head;  the  neck;  thorax  and  thoracic  viscera;  abdomen,  abdominal  viscera 
and  peritoneum;  the  ischio-rectal  fossa;  the  axillary  space;  the  ante-cubital 
space;  Scarpa's  triangle  or  the  femoral  trigone;  Hunter's  canal  or  the  ad- 
ductor canal;  the  popliteal  space;  the  inguinal  rings  and  inguinal  canal; 
the  femoral  rings  and  femoral  canal;  hernia;  the  extremities  compared; 
review  notes;  points  for  compression  of  larger  arteries  of  the  body  .;    ...   292 

CHAPTER  XXIII. 
REFERENCE  TABLES. 

The  systemic  arteries;  names  of  systemic  arteries  and  veins  according  to  the 

B.  N.  A 311 

Glossary 321 

Index 331 


ANATOMY  AND  PHYSIOLOGY 
FOR  NURSES. 


INTRODUCTORY. 


Anatomy  deals  with  the  structure  of  the  body  in  its  different  parts; 
physiology  teaches  the  uses  or  ftmctions  of  those  parts. 

Plan  of  Study. 

We  shall  study  first  the  framework  of  the  body — the  bones 
which  give  support  to  all  other  structures,  with  the  joints  by  which 
they  are  held  together,  either  loosely  or  firmly;  and  the  muscles 
by  which  they  are  moved  and  still  further  connected. 

Afterw^ard  will  be  presented  the  organs  or  viscera  (which  are 
enclosed  in  the  two  general  cavities  formed  by  the  bones  and  muscles) 
with  their  nerve  supply,  and  the  system  of  vessels  by  which  the  entire 
body  receives  its  nutriment.  We  shall  see  that  all  these  parts  are 
wrapped  in  delicate  connective  tissue,  and  held  in  place  by  bands 
and  sheaths  of  the  same  substance.  The  muscles  are  stretched  upon 
the  bones,  the  firm  layers  and  partitions  of  deep  fascia  bind  them 
in  place,  the  wrapping  of  superficial  fascia  keeps  them  warm  and 
flexible,  and  the  skin  or  integument  makes  an  elastic  and  sufficient 
covering  for  the  whole. 

The  study  of  the  nerves  by  which  these  structures  receive  their 
stimulus,  and  the  action  and  interaction  of  the  various  parts, 
will  follow. 

The  organs  of  the  special  senses  receive  attention,  and  the  last 
section  is  devoted  to  a  review  of  the  several  regions  of  the  body  which, 
it  is  hoped,  will  prove  interesting  and  profitable. 

Anatomic  Use  of  Terms. 

The  anatomic  position  is  that  with  the  face  toward  the  ob- 
server and  the  palms  turned  forward,  and  the  terms  anterior,  posterior, 

I 


2  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

right,  left,  etc.,  are  to  be  understood  with  this  position  in  mind. 
Thus,  the  anterior  surface  of  the  hand  is  always  the  palm;  and,  if 
we  speak  of  any  part  as  situated  to  the  right  we  mean  that  it  is 
nearer  to  the  right  side  of  the  body  which  we  are  studying  (which 
for  convenience  we  will  call  the  "subject"),  but  it  has  no  relation 
whatever  to  the  right  side  of  the  student.  Of  course  the  words 
superior  and  inferior  are  easily  understood,  but  the  use  of  the  words 
medial  and  lateral  (formerly  internal  and  external)  requires  special 
mention.  Imagine  a  line  drawn  through  the  middle  of  the  head 
and  trunk  and  striking  the  floor  between  the  feet,  thus  dividing 
the  body  into  right  and  left  halves.  This  is  called  the  median  line. 
Any  part  or  surface  of  one-half  of  the  body  is  said  to  be  medial  to 
another  part  if  it  is  nearer  the  median  line  while  in  the  anatomic 
position,  or  lateral  to  another  part  if  it  is  farther  from  the  median 
line. 

All  of  these  terms  once  applied  to  a  part  of  the  body  belong  to 
it  always.  For  example,  the  little  finger  is  always  medial  to  the 
others  and  the  great  toe  is  likewise  medial,  because  these  relations 
are  established  once  for  all  while  the  subject  is  in  the  anatomic 
position.  Likewise,  the  palm  is  the  anterior  surface  of  the  hand  even 
if  it  be  temporarily  turned  backward. 

The  words  exterior  and  interior  are  applied  to  the  parts  of  the 
body  which  are  on  the  surface  or  within,  respectively. 

Proximal,  means  nearer  to  the  head;  distal,  farther  from  the 
head.  Thus  we  may  speak  of  the  proximal  end  of  the  finger,  or 
the  distal  end  of  a  toe,  or  the  proximal  end  and  distal  end  of  an 
arm  or  a  leg. 


TISSUES  AND  MEMBRANES  OF  THE  BODY. 

The  simplest  form  of  living  matter  is  protoplasm.  A  living  cell 
may  be  nothing  more  than  a  definite  quantity  of  protoplasm  (called 
cytoplasm  or  bioplasm)  or  it  may  be  more  complex,  having  a  nucleus^ 
when  it  is  said  to  be  nucleated,  and  it  may  have  a  nucleolus  within 
the  nucleus.  A  nucleated  cell  is  capable  of  forming  new  cells  by 
the  division  of  its  substance,  the  division  always  beginning  in  the 
nucleus. 

Sometimes  the  cell  is  enveloped  by  a  thin  membrane  called  the  cell  wall. 


TISSUES    OF    THE    BODY  3 

Tissue. — Any  collection  of  cells  held  together  by  intercellular 
substance  is  a  tissue.  The  various  tissues  of  the  body  are  composed 
of  cells  (and  intercellular  substance)  which  are  developed  in  special 
ways;  for  example: 

Muscle  tissue  is  composed  largely  of  cells  which  are  highly 
developed  in  the  power  to  contract. 

Nerve  tissue,  of  cells  which  are  particularly  sensitive  to  special 
kinds  of  stimulus. 

Connective  tissue  is  the  fibrous  soft  framework  of  the  entire 
body— the  connecting  structure  by  means  of  which  all  of  its  parts 
are  held  together.     (Fig.  i.) 


Fig.  I. — Connective-tissue 
Bundles  of  Various  Thick- 
nesses OF  THE  Intermuscular 
Connective  Tissue  of  Man. 
X  240. — (Stohr.) 


In 

super- 
posed 
layers 


Fig.  2. — ^Adipose  Tissue. — (Stohr.) 


Under  this  heading  are  included  the  following  varieties: 
Fibrmis  tissue,  a  form  of  connective  tissue  containing  slender 

white  fibers,  closely  packed  together. 
Areolar  tissue,  containing  the  same  kind  of  fiber  cells  loosely 

woven  into  a  network  (often  called  cellular  tissue). 
Adipose  tissue,  a  variety  of  areolar  tissue  with  cells  containing 

fat.     (Fig.  2.) 
Elastic  tissue,  a  form  of  connective  tissue  containing  many 

elastic  fibers,  pale  yellow  in  color.     (Fig.  3.) 
Osseous  tissue,  composed  largely  of  cells  having  the  power  to 

utilize  mineral  substances  of  the  blood  in  the  formation 


ANATOMY  AND   PHYSIOLOGY    FOR    NURSES. 

of  bone.      (The  intercellular  substance  is  filled  with  min- 
eral matter.)      (Figs.  6  and  7.) 
Cartilage,  a  form  of  connective  tissue  with  firm  white  elastic 
substance     (intercellular    substance)     between    its    cells. 


Fig.  3. 


/'x 


-Elastic  Fibers.     X  560.     Very  thick  elastic  fibers  /,  from  ligamentum 
nuchse  of  ox;  b,  connective-tissue  bundles. — (Stohr.) 

Many  cartilages  are  covered  with  a  thin  membrane  called 
perichondrium,  similar  to  the  periosteum  of  bones  (see 
page  10). 

.  The  principal  varieties  are: 

Hyaline  cartilage  which   has  few   cells  and 

much  intercellular  substance.     (Fig.  4.) 

WJtite  fibro-cartilage  which  contains  many  white 

S- —  fibers,  giving  to  it  additional  strength. 

Yellow  or  elastic  fibro-cartilage  which  contains 

elastic  fibers  giving  additional  elasticity. 

'^  Note. — Most  bones  are  formed  in  cartilage.     (See 

^      _  Ossification  page  11.) 

Fig.  4.^Hyaline  t^.ii-i. 

Cartilage.  Epithelial  tissue  forms  the  surface  layers  of 

the  body  both  within  and  without.  It  is  com- 
posed of  layers  of  cells  resting  upon  a  base  of  the  simplest  possible 
substance,  which  holds  the  cells  together  and  which  bears  vessels 
and  nerves  for  their  use.  The  form  of  epithelial  cells  varies  with 
their  location  and  use  or  function.     (Fig.  5.) 

The  epithelium  of  the  exterior  of  the  body  is  formed  by  flattened 
cdls,  arranged  in  few  or  many  layers  according  to  the  degree  of 


EPITHELIAL    TISSUES.  ^ 

friction  or  pressure  to  which  the  skin  of  the  part  may  be  exposed. 
The  covering  thus  formed  varies  therefore  in  thickness,  from  that 
of  the  deKcate  covering  of  the  lips  to  the  tough  sole  of  the  foot. 

The  epithelium  of  interior  surfaces  is  quite  different.  Its  cells 
may  be  flattened,  spherical,  cuboid  or  columnar  in  shape  and  it  is 
always  moist. 


Fig.  5. — Epithelial  Cells  of  Rabbit,  Isolated.  X  560.  i.  Squamous  cells 
(mucous  membrane  of  mouth).  2.  Columnar  cells  (corneal  epithelium).  3.  Columnar 
cells,  with  cuticular  border  5,  (intestinal  epithelium).  4.  Ciliated  cells;  h,  cilia 
(bronchial  epithelium). — (Stohr.) 


In  the  lining  of  the  air  passages  the  epithelial  cells  are  ciliated,  that  is,  they 
bear  tiny  hair-like  projections  of  their  substance  called  cilia,  which  are  in  con- 
stant waving  motion,  always  in  the  same  direction,  sometimes  slow,  sometimes 
rapid. 

In  the  digestive  organs  the  epithelial  layer  plays  an  important  part  in  the 
formation  of  digestive  fluids,  and  also  in  the  absorption  of  digested  food. 

In  the  lining  of  closed  cavities  it  assists  in  the  formation  of  the  fluids  which 
they  contain  (example,  the  pleura). 

Included  under  this  heading  are: 
Gland  tissue,  where  a  layer  of  cells  has  the  power  to  form 

a    special    substance    from    the    blood.     {Adenoid    tissue 

resembles  gland  tissue.) 
Mucous  membranes,  which  line  all  interior  surfaces  to  which 

air  has  access.     Their  special  cells  produce  a  clear  thick 

fluid  called  mucus  which  keeps  the  surfaces  moist. 
Serous  membranes ,  which  line  the  closed  cavities  of  the  body. 

They  are  themselves  closed  sacs  containing  a  clear  thin 

fluid  called  serum  which  prevents  the  surfaces  from  rubbing 

together. 
Synovial  membranes,  which  line  the  interior  of  movable  joints; 

they  contain  a  thick  fluid  called  synovia  which  like  serum 

prevents  friction. 


6  ANATOMY  AND    PHYSIOLOGY   FOR    NURSES. 

The  epithelial  lining  of  the  heart  and  blood-vessels,  serous  membranes, 
and  lymph  vessels,  is  called  endothelium. 

Clinical  notes. — Mucous  membranes  are  w^ell  supplied  with  blood-vessels 
and  bleed  freely  when  wounded,  as  seen  in  operations  upon  the  nose  and  throat. 

An  accumulation  of  serum  in  the  large  serous  membrane  of  the  abdomen 
causes  the  condition  called  ascites  (a  variety  of  dropsy). 

The  processes  of  secretion  and  excretion  are  carried  on  through 
epitheHal  cells. 

Secretion  is  the  process  of  separating  substances  from  the  blood 
(generally  in  fluid  form).  Such  substances  if  useful  to  the  body 
are  called  secretions ;  if  they  are  waste  matters  to  be  thrown  off  or 
eliminated,  they  are  called  excretions. 

Secreting  organs — mucous  and  serous  membranes,  all  glands. 

Excreting  organs— -hing^^  kidneys,  liver,  cutaneous  glands. 

To  summarize  the  functions  of  epithelial  tissues — they  are  pro- 
tective, secretory,  excretory,  absorptive. 

An  organic  substance  is  a  substance  formed  by  living  cells, 
whether  they  are  single  or  arranged  together  in  organs.  Organic 
substances  disappear  in  burning. 

An  organ  is  any  part  of  the  body  designed  for  a  special  function 
or  use;  it  may  be  composed  of  several  kinds  of  tissue.  An  organ 
in  the  interior  of  the  body  (internal  organ)  is  called  a  viscus  (pleural, 
viscera).     Examples,  heart,  lungs. 

A  system  is  composed  of  a  number  of  organs  of  similar  structure. 
Examples,  the  muscular  system,  the  nervous  system. 

An  apparatus  is  composed  of  a  number  of  organs  of  like  or 
different  structures,  so  arranged  and  associated  that  their  action 
together  will  serve  a  special  purpose.  Example,  the  digestive 
apparatus. 

Metabolism. — ^This  term  is  used  to  express  in  one  word  the 
related  processes  of  building  up  and  breaking  down  which  are  con- 
stantly going  on  in  all  living  cells. 

The  cell  appropriates  materials  and  combines  them  to  perfect 
itself;  in  the  exercise  of  its  function  it  uses  up  some  portion  of  its 
substance  and  so  must  be  again  built  up,  to  be  again  pulled  apart 
• — in  endless  repetition. 

Cell  action  in  some  tissues  results  principally  in  liberating  heat  and  in 
hody  movement,  as  in  muscles.  In  others  it  forms  new  compounds  for  other  cells 
to  use — for  example,  the  liver  cells  form  glycogen;  the  gastric  glands  secrete 


METABOLISM.  7 

gastric  juice,  etc.  Again,  certain  cells  combine  waste  matters  to  get  them  into 
shape  for  other  organs  to  excrete,  for  example,  the  formation  of  iirea  in  the  liver. 
In  this  way  food  materials  are  used  for  different  purposes  and  worked  over  in 
different  tissues  until  waste  alone  remains. 

These    examples   (and   many   more   which    might   be    given)  illustrate    the 
metabolism  which  is  constantly  taking  place  in  the  body. 


CHAPTER  I. 

BONE  TISSUE  AND  BONE  CLASSIFICATION, 
ARTICULATIONS. 


0)  2 


His 


Bone  tissue  is  conspicuously  a  hard  tissue.  This  hardness  is 
due  to  the  mineral  or  inorganic  substances  which 
it  contains.  They  are.  mostly  phosphate  and  car- 
bonate of  lime  and  form  two-thirds  of  the  weight 
of  an  adult  bone.  The  remaining  one-third  is 
composed  of  organic  or  animal  substances,  con- 
sisting of  vessels,  marrow,  hone  corpuscles,  and 
gelatinous  matter. 

The  mineral  portion  alone  may  be  seen  in  a 
bone  which  has  been  burned,  thus  destroying 
the  organic  substances.  This  leaves  the  bone 
still  hard,  but  very  brittle  and  easily  crushed. 
The  pale  grayish  color  of  a  burned  bone  is 
noticeable,  the  result  of  the  loss  of  all  the  marrow 
and  blood  which  it  contained  before,  and  which 
gave  it  a  pinkish  tinge. 

The  organic  portion  of  a  bone  may  be  shown 
by  immersing  it  in  dilute  hydrochloric  acid  for 
a  few  days.  The  mineral  salts  will  be  thus  dis- 
solved out,  leaving  the  flexible  and  elastic  organic 
portion  which  still  retains  the  shape  of  the  bone. 
A  long  bone  after  the  lime  salts  are  removed  in 
this  way,  is  said  to  be  decalcified,  and  may  be 
bent  and  twisted,  or  even  tied  in  a  knot. 

By  these  experiments  it  i?  seen  that  the 
mineral  matter  gives  hardness  to  a  bone,  while 
the  animal  matter  gives  flexibility  and  elasticity. 
The  proportions  of  the  two  kinds  of  substance 
vary  at  different  ages.  The  bones  of  a  child 
SectJon^  OT^A^ToNG  ^^^  ^^^^  bccausc  they  have  not  enough  mineral 
Bone.— (Testut.)  matter  to  make  them  hard,  while  the  bones  of 


0%^^i 


BONE    TISSUE   AND    BONE    CLASSIFICATION.  9 

an  aged  person  are  brittle,  because  they  no  longer  contain  sufficient 
animal  matter  to  keep  them  elastic. 

The  hardest  part  of  any  bone  is  at  its  surface;  it  is  white  in  color 
like  ivory,  and  is  called  compact  bone  tissue.  The  deeper  part  is 
porous,  and  is  therefore  called  spongy  tissue  (also  named  cancellous 
tissue,  because  its  appearance  suggests  lattice  work).     (See  Fig.  6.) 

Compact  tissue  is  most  abundant  on  the  shafts  of  the  long  bones, 
which  by  their  situation  in  the  extremities  are  exposed  to  external 
violence,  and  therefore  need  especial  strength  for  resistance.  Since 
it  is  important  that  the  bones  be  slender  as  well  as  strong,  these  two 
results  are  gained  by  packing  the  bone  tissue  as  closely  as  possible. 

Cancellous  tissue  is  more  abundant  in  the  parts  of  bones  where 
extent  of  surface  is  desirable.  For  example,  the  enlarged  extremities 
of  long  bones  are  composed  of  cancellous  tissue  covered  with  a  thin 


Periosteum 

Outer  ground  lamellae 

Haversian  canals 


Haversian  lamellae 

Interstitial  lamellas 
Inner  ground  lamellas 

Marrow 


Fig.  7. — From  a  Cross-Section  of  a  ^SIetacarp  of  Man.     X  50.     The  Haversian 
canals  contain  a  little  marrow  (fat-cells). — (Stohr.; 


compact  layer;  thus  they  can  give  attachment  to  many  tendons  and 
ligaments,  v/hile  the  spongy  character  of  the  bone  prevents  increase 
in  weight. 

The  marrow  of  bones  is  contained  in  the  spaces  of  cancellous 
tissue,  where  it  is  thin  and  red,  and  in  little  canals  running  through 
the  bone  substance.  Under  the  microscope  may  be  seen  small 
channels  in  the  compact  tissue  called  Haversian  canals,  which  con- 
tain minute  vessels  and  a  little  marrow.  A  large  canal  called  the 
medullary  canal  runs  in  the  shaft  of  each  long  bone,  containing 
firm  yellow  marrow  and  larger  vessels. 


lO  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

Articular  surface  of  bone  is  that  portion  which  enters  into  the 
formation  of  a  movable  joint.  It  consists  of  a  very  compact  tissue 
called  the  articular   layer  or  articular  lamella. 

Surface  Markings  of  Bone. 

Any  inequality  of  the  surface  of  a  bone,  whether  it  be  an 
elevation  or  depression,  or  an  opening,  is  called  a  "marking." 
The  most  prominent  elevations  often  occur  where  the  muscles  are 
attached  to  the  periosteum  (owing  partly  to  the  calcification  of 
these  attachments);  and  the  greatest  enlargements  of  bones  are 
at  their  extremities,  where  they  form  important  joints. 

A  process  is  a  decided  projection;  the  larger  processes  are  called 
tuberosities,  small  ones,  tubercles. 

A  spine  is  usually  a  long  or  a  sharp  projection. 

A  crest  is  a  prominent  border;  it  may  be  rather  broad. 

A  condyle  is  a  rounded  articular  eminence. 

A  fossa  is  a  depression  or  concavity. 

A  foramen  is  a  hole  through  a  bone. 

Periosteum. 

There  is  no  such  thing  as  bare  bone  in  the  normal  state;  all 
bones  are  closely  covered  more  or  less  completely  with  a  strong 
fibrous  membrane  called  periosteum.  This  membrane  is  essential 
to  the  life  of  the  bone,  because  many  blood-vessels  which  nourish 
it  lie  in  the  periosteum  until  they  become  divided  into  minute 
branches  which  then  enter  the  bone  tissue. 

The  articular  surface  of  bone  is  the  only  portion  which  is  not 
covered  with  periosteum. 

A  bruise  of  sufficient  violence  will  so  injure  the  periosteum  that 
it  no  longer  serves  for  the  purpose  of  nutrition,  and  that  area  of 
bone  immediately  underneath  the  injured  membrane  dies  from 
want  of  food,  and  becomes  "dead  bone"  (the  process  is  called 
necrosis).  The  sensation  imparted  by  a  probe  which  touches 
dead  bone  is  that  of  roughness,  and  is  distinctly  different  from  the 
feeling  of  sound  bone  with  its  smooth  covering  of  periosteum. 
A  similar  membrane  called  endosteum  lines  the  canal  in  the  shaft 
of  long  bones.     It  bears  the  "nutrient"  artery  which,  in  the  cavity 


OSSIFICATION. 


II 


of  the  shaft,  divides  into  two  branches  running  in  the  endosteum 
toward  the  two  extremities. 

The  deep  layers  of  the  periosteum  contain  bone-forming  cells. 
(See  Ossification.) 


Classification  of  Bones  According  to  Shape. 

According  to  differences  of  shape  and  arrangement  of  their 
tissue,  bones  are  classified  as  long,  short,  flat,  and  irregular.  A 
long  bone  has  always  a  shaft  of  compact  tissue,  and  two  enlarged 
extremities  of  cancellous  tissue  with  a  thin  compact  covering.  The 
shaft  is  hollow,  containing  yellow  marrow,  this  cavity  being  called 
the  medullary  canal. 

A  short  bone  has  neither  shaft  nor  extremity; 
it  is  composed  of  cancellous  tissue  with  a  thin  com- 
pact covering. 

Aflat  bone  is  arranged  in  layers,  two  of  compact 
tissue  with  one  of  spongy  or  cancellous  tissue  be- 
tween them. 

An  irregular  bone  conforms  to  no  special  defi- 
nition. 


Remarks. — In  no  part  of  anatomy  is  it  more  important 
that  the  student  should  learn  the  structures  from  the  actual 
specimens  than  in  the  division  called  osteology.  The  bodies 
are  to  be  studied,  not  the  book.  It  is  supposed  that  with 
the  bone  in  the  hand  the  student  will  use  the  book  as  a  key, 
by  means  of  which  she  will  become  acquainted  with  the 
names  of  its  parts  and  their  uses.  The-  habit  of  studying 
the  human  body  itself  rather  than  the  description  of  it, 
cannot  be  too  soon  nor  too  firmly  established. 


OSSIFICATION. 


Fig.  8. — Right 
Femur,  Anterior, 
SHOWING  Extremi- 
ties OR  Epiphyses, 
AND  Shaft  or  Di- 
APHYSis. — (Morris.) 


Ossification  is  the  formation  of  bone  from 
cartilage  or  membrane  by  the  deposit  of  mineral 
substances,  mostly  salts  of  lime.  Flat  bones  de- 
velop in  membrane;  others  in  cartilage. 

The  deposit  of  mineral  matter  begins  in  small  spots,  forming 
centers  of  ossification  which  gradually  increase  in  size  until  the 
entire  bone  is  completed.  Long  bones  have  always  three  centers  at 
first — one  for  the  shaft,  and  one  for  each  extremity — others  appear- 


12  ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 

ing  later,  at  different  dates.  (The  extremities  are  named  epiphyses, 
the  shaft  being  the  diaphysis)  (see  Fig.  8).  The  principal  parts  of 
a  bone  are  ossified  separately,  uniting  wth  each  other  after  all  are 
developed.  Ossification  begins  before  birth  in  all  bones  except 
the  coccyx,  those  of  the  carpus,  and  four  in  the  tarsus;  but  many 
bones  remain  in  two  or  more  pieces  during  childhood  and  youth. 

The  periosteum  of  bone  has  an  inner  layer  in  which,  also,  the 
process  of  ossification  goes  on.  Consequently,  when  it  becomes 
necessary  to  remove  a  portion  of  bone,  if  it  can  be  done  without 
taking  the  periosteum  away  the  bone  will  re-form.  This  has 
occurred  many  times,  particularly  in  the  case  of  the  mandible. 

The  nutrition  of  bone.— Bones  have  a  free  blood  supply  from 
a  network  of  small  arteries  in  the  periosteum.  One  special  artery, 
larger  than  the  others,  enters  the  nutrient  canal  which  leads  to  the 
interior  of  the  shaft  (this  vessel  is  called  the  nutrient  artery). 

THE  HUMAN  SKELETON. 

The  skeleton  of  the  body  comprises  200  bones,  as  follows: 

In  the  cranium 8 

In  the  face 14 

In  the  spinal  column ■.  .  .  24 

In  the  pelvis 4 

In  the  upper  extremities 64 

In  the  lower  extremities. 60 

Ribs 24 

Os  hyoides i 

Sternum i 


These  are  joined  together  or  articulated  to  form  the  hard,  strong 
framework  of  the  body — the  natural  skeleton. 

In  addition  to  these,  there  are  four  bones  in  each  ear  called  ossicles,  or 
"little  bones." 

According  to  their  location  in  the  body  they  are  classified  as 
follows :  Bones  of  the  Head  and  Neck,  Trunk,  Extremities. 

The  bones  of  the  head  form  the  skull,  which  supports  the 
face  and  the  organs  of  special  sense,  and  securely  encloses  the 
brain  within  its  cavity.  The  bones  of  the  neck  connect  the  head 
with  the  trunk,  and  support  the  tongue  and  various  other  structures. 


THE   HUMAN    SKELETON. 


13 


The  bones  of  the  trunk  assist  to  form  a  cavity,  divisible  into 
three  portions — the  thorax,  the  abdomen,  and  the  pelvis. 


Tarsus 
Metatarsus 
'halanges 


Fig.  9. — Bony  Skeleton. — (Gould's  Illustrated  Dictionary.) 

The  bones  of  the  four  extremities  contribute  the  solidity  and 
strength  which  are  necessary  for  their  uses  in  various  positions  of 
the  body. 


14 


ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 


ARTICULATIONS  (ARTHROSES). 

Articulations  are  formed  when  two  or  more  bones  are  con- 
nected together,  or  when  bone  and  cartilage  are  joined.  They  may 
be  immovable,  or  movable. 


Immovable  Joints  (Synarthroses). 

In  these  the  bones  are  held  together  firmly  by  fibrous  tissue, 
sometimes  by  a  thin  layer  of  cartilage  which  becomes  calcified  in 
later  life. 

The  best  examples  of  immovable  joints  are  found  in  the  skull, 
t  .      where  the  flat  bones  are  joined  at  their 

edges,  forming  sutures.     (See  page  i6, 
Fig.  II.) 


Movable  Joints  (Diarthroses). 

In  these  the  bones  are  not  closely 
joined,  but  are  loosely  connected  by 
ligaments  which  allow  freedom  of  move- 
ment between  the  surfaces.  They  are 
best  studied  in  the  extremities,  where 
all  varieties  of  movable  joints  are  found. 
The  essential  structures  in  a  mova- 
ble joint  are  four  in  number:  Articular 
hone,  articular  cartilage,  ligaments,  syno- 
vial membrane  with  synovia. 

The  surfaces  of  bone  which  are  to  be 
connected  together  (articular  surfaces) 
are  made  of  a  specially  hard  compact 
tissue  called  articular  bone.  It  is  smoother 
than  other  portions  of  the  bone  and  easily  recognized  by  the  eye. 
It  has  no  periosteum,  but  is  covered  by  firm  white  hyaline  cartilage 
— the  articular  cartilage. 

To  hold  the  bones  together,  bands  or  cords  of  white  fibrous  tissue 
are  provided,  strong  and  flexible,  but  not  elastic.  They  are  called 
ligaments.  The  ligaments  pass  from  one  bone  to  the  other  on  every 
side  of  the  joint,  like  a  capsule,  completely  enclosing  it,  and  the 
capsule  thus  formed  is  lined  by  synovial  membrane,  so  named  because 


Fig.  io. — Illustration 
Showing  Essential  S  t  r  u  c  - 
TURES  IN  A  Movable  Joint 
(Diagrammatic.) 


ARTICULATIONS.  I5 

it  secretes  a  fluid  called  synovia  (the  lubricating  fluid  or  "joint- 
oil")  which  resembles  in  appearance  the  white  of  egg  and  prevents 
friction. 

The  synovial  membrane  not  only  lines  the  capsule  but  is  attached 
to  the  margins  of  the  articular  cartilages. 

Seven  varieties  of  movement  are  allowed  by  these  joints.  They 
are: 

Flexion,  or  bending. 

Extension,  or  straightening. 

Rotation,  or  rolling. 

Circumduction,  a  free  sweeping  movement  in  a  circle. 

Abduction,  or  moving  away  from  a  middle  line. 

Adduction,  or  moving  toward  a  middle  line, 

Gliding  (which  explains  itself). 

Movable  joints  are  classified  according  to  the  movements  of 
individual  joints,  or  by  peculiarities  of  structure.  The  most  im- 
portant are  the  following: 

Class.  Motions.  Example. 

Hinge  (ginglymus) Flexion  and  extension.  .  .  .  Elbow,  Knee. 

Ball    and  socket  (Enar- 

throsis).    In  all  directions Shoulder,  Hip. 

Pivot  (Trochoides) Rotation  within  a  ring. .  .  .  Head  of  Radius. 

Rotation  of  ring  around  a 

pivot .  . Atlas  and  axis. 

Arthrodia Gliding Carpal  joints. 

There  are  other  joints  in  which  motion  is  so  slight  that  they  are 
not  classed  as  movable,  nor  do  they  possess  a  cavity  containing 
synovia.  They  have  been  well  described  by  the  term  yielding. 
In  these  the  bones  are  usually  connected  by  fibro-cartflage  discs. 
Examples  are  found  in  the  joints  of  the  pelvis  (page  46)  and  in  the 
spinal  column  (page  38). 


CHAPTER  II. 
BONES  AND  ARTICULATIONS  OF  THE  SKULL. 

The  skull  includes  the  cranium  and  face. 

BONES  OF  THE  CRANIUM,  8. 


Frontal i 

Occipital I 

Temporal 2 


Parietal 2 

Ethmoid i 

Sphenoid i 


Frontal  bone  {os  frontale). — In  the  anterior  part  of  the  skull, 
shaped  like  a  cockle-shell,  and  consisting  of  the  frontal  part,  or 
forehead,  the  two  orbital  parts,  and  the  nasal  part.     The  frontal 


GLABELLA, 


ANTERIOR    NASAL 
SPINE 


PROSTHIO 


Fig.  II. — The  Skull. — (Gerrish.) 

part  {squama  frontalis)  is  flat  in  structure,  and  unites  above  with 
the  parietal  bones.  This  part  is  bounded  below  by  a  prominent 
border    forming    the   two    supraorbital    margins.     At  the   medial 

16 


BONES    OF    THE    CRANIUM. 


17 


third  of  each  margin  is  a  supraorbital  notch  (sometimes  foramen) 
for  the  supraorbital  nerve,  artery,  and  vein.  Just  above  the  margins 
are  the  superciliary  arches,  which  bear  the  eyebrows  and  mark  the 
position  of  spaces  in  the  frontal  bone  called  the  fro^ital  sinuses. 
These  sinuses  begin  to  develop  at  the  age  of  seven  years  and  grow 
larger  as  time  advances.  They  communicate  with  the  nose,  and 
contain  air.     The  smooth  space  between  the  eyebrows  is  the  glabella. 

The  nasal  part  is  just  below  the  glabella. 

The  orbital  parts  (or  plates)  of  the  frontal  bone  are  so  called 
because  they  are  in  the  roof  of  the  orbits,  or  eye-sockets;  the  space 
between  these  parts  is  occupied 
by  the  ethmoid  bone  and  is 
called  the  ethmoid  notch.  Just 
underneath  the  lateral  part  of 
the  superior  margin  of  the  orbit 
is  a  small  fossa  (the  lacrimal 
fossa),  containing  the  lacrimal 
gland,  where  the  tears  are 
formed. 

At  birth  the  frontal  bone  is 
in  halves — right  and  left — which 
become  united  in  early  life. 

Occipital  bone   (os  occipi- 
tale).— At  the  back  of  the  skull 
and  consisting  of  two  portions:  squamous  (scale-shaped)  and  basal 
(Figs.  II  and  20). 

The  squamous  portion  {squama  occipitalis)  is  flat  in  structure, 
triangular  in  shape,  and  joined  to  the  parietal  bones.  The  most 
prominent  point  on  the  back  of  the  skull  is  on  this  portion,  and 
is  called  the  occipital  protuberance  or  inion. 

The  basal  portion  bends  forward,  extending  far  enough  toward 
the  front  to  form  the  roof  of  the  throat.  This  portion  presents  a 
large  opening  called  the  foramen  magnum  (or  great  foramen),  which 
transmits  the  spinal  cord.  At  the  sides  of  the  foramen  magnum  are 
two  smooth  prominences,  called  the  occipital  condyles,  which  rest 
upon  the  first  bone  of  the  spinal  column,  whereby  the  nodding 
movement  of  the  head  is  permitted. 

The  inner  surface  of  this  bone  has  broad  grooves  for  the  transverse  sinuses 
(lateral  sinuses);  also  one  for  the  sagittal  sinus  (superior  longitudinal  sinus). 
2 


Fig.  12. — Frontal  Boxe,  showing  that 
IT  Originates  in  Halves. — (Alorris.) 


i8 


ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 


Temporal  bones  (ossa  temporales). — Right  and  left;  situated  at 
the  sides  and  base  of  the  skull.     (See  Figs,  ii  and  13.) 

Each  temporal  bone  consists  of  four  portions — the  squamous, 
the  mastoid,  the  petrous,  and  the  tympanic. 

The  squamous  portion  {squama  temporalis)  is  fiat,  and  presents 
the  zygomatic  process  in  the  form  of  a  ridge  running  forward  in  front 
of  the  ear  to  the  cheek.  Below  the  beginning  of  this  process  is  the 
canal  leading  into  the  ear  and  called  the  external  auditory  meatus  \ 
just  in  front  of  that  is  the  mandibular  fossa,  where  the  lower  jaw- 
bone, or  mandible,  is  joined  to  the  temporal  bone  (Fig.  11). 


Fig.  13. — Pasietal,  Temporal,  and  Sphenoid  Bones; 
Posterior  Aspect. 
I,  Body  of  sphenoid  bone;  2,2,  greater  wing  and  squamous  portion  of  sphenoid  bone; 
3,  3,  parietal  bones;  4,  4,  mastoid  process  of  temporal  bones. — (Gould's  Dictionary.) 
The  occipital  bone  occupies  the  space  included  between  these  bones. 

The  mastoid  portion  forms  the  prominence  behind  the  ear  and 
terminates  in  the  mastoid  process,  which  contains  a  number  of  small 
cavities,  the  mastoid  cells.  They  all  communicate  with  the  middle 
ear,  and  mastoid  disease  may  therefore  follow  an  infection  of  the 
middle  ear. 

The  inner  surface  of  this  portion  shows  the  sigmoid  groove  for  the  transverse 
sinus. 

The  petrous  portion  is  exceedingly  hard,  like  stone,  hence  its 
name.     A  slender  point  of  bone,  called  the  styloid  process,  is  seen 


BONES    OF    THE    CRANIUM.  I9 

on  its  lower  surface,  and  the  carotid  artery,  on  its  way  to  the  brain, 
passes  through  the  carotid  canal,  which  is  in  this  portion. 

The  petrous  bone  contains  the  greater  part  of  the  ear,  and  the 
internal  auditory  canal  for  the  auditory  nerve,  or  nerve  of  hearing, 
is  on  its  posterior  surface  (seen  within  the  skull). 

The  tympanic  portion  forms  the  greater  part  of  the  external  auditory 
meatus,  or  canal. 

Parietal  bones  {ossa  parietales). — Right  and  left,  situated  at 
the  top  and  sides  of  the  head,  and  so  named  because  they  form 
the  sides  or  ivalls  of  the  skull.  They  are  fiat  in  structure,  and 
nearly  square  in  shape,  and  the  four  borders  are  called  sagittal, 
squamous,  frontal,  and  occipital  (Figs,  ii  and  13). 

At  the  extremities  of  the  borders  are  the  angles — the  frontal 
and  occipital  angles  above,  and  the  sphenoid  and  mastoid  angles 
below.  The  most  prominent  point  on  the  side  of  the  skull  is  near 
the  center  of  the  parietal  bone  and  is  called  the  parietal  eminence. 

On  the  inner  surface  of  this  bone  well-marked  grooves  are 
seen  for  the  middle  meningeal  artery,  and  depressions  for  the  con- 
volutions of  the  brain. 

Ethmoid  bone  {os  ethmoidale). — Situated  between  the  orbits 
and,  therefore,  in  the  upper  part  of  the  nose.  (For  illustration  see 
pages  29,  30.) 

It  consists  principally  of  two  lateral  portions  formed  of  spongy 
bone,  and  containing  the  ethmoid  cells  or  sinuses.  These  portions 
are  called  ethmoid  labyrinths.  They  are  in  the  walls  of  the 
nasal  cavity,  and  the  cells  open  into  it,  therefore  they  contain  air. 
The  labyrinths  are  attached  to  the  borders  of  the  horizontal 
plate,  situated  in  the  roof  of  the  nose  and  perforated  for  the  passage 
of  the  nerves  of  smell. 

The  upper  part  of  the  nasal  septum,  which  .divides  the  nasal 
cavity  into  two  parts,  is  formed  by  the  vertical  plate  of  the  ethmoid, 
which  hangs  from  the  horizontal  plate,  and  is,  therefore,  between 
the  two  labyrinths  (Fig.  25). 

Two  of  the  turbinated  boner,  (superior  and  middle)  are  seen  projecting 
from  the  medial  surface  of  the  labyrinths  (Fig.  24).  (For  description  of  in- 
ferior turbinated  see  page  22.) 

Sphenoid  bone  ios  sphenoidale). — Immediately  behind  the 
ethmoid,  to  which  it  is  joined.     Its  shape  resembles  a  bat  with 


20  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

the  wings  spread  (Figs,  ii  and  13).  It  consist  of  a  body,  wings,  and 
two  pterygoid  processes.  The  body  is  joined  to  the  ethmoid  in  front, 
and  to  the  occipital  behind.  It  is  hollow,  and  its  two  cavities  (called 
the  sphenoid  sinuses)  communicate  with  the  nose.  The  wings, 
two  pairs — greater  and  lesser — extend  outward  from  the  body  at 
about  the  level  of  the  orbits.  The  optic  foramen,  for  the  optic 
nerve,  is  in  the  lesser  wing. 

The  processes  extend  downward  from  the  body,  completing 
the  back  part  of  the  sides  of  the  nose. 

Note. — The  lateral  extremities  of  the  greater  wings  may  be  seen  at  the  sides 
of  the  skull,  between  the  frontal  and  temporal  bones;  the  sphenoid  is  thus 
wedged  in  behind  the  face,  between  it  and  the  other  cranial  bones.  (The  name 
sphenoid  signifies  wedge-like.) 

ARTICULATIONS  OF  THE  CRANIUM. 

The  joints  of  the  cranium  are  called  sutures.  Most  of  them 
are  formed  by  the  interlocking  of  irregular  edges  of  the  bones  held 
firmly  together  by  fibrous  tissue  between  them.  Sometimes  the  edges 
resemble  saw-teeth  in  form,  and  then  the  suture  is  dentated  or 
serrated.  Sometimes  the  edges  are  smooth  and  overlap  each  other, 
and  sometimes  one  fits  between  two  others;  but  they  are  always 
immovable.     (For  illustration,  see  Fig.  11.) 

The  sutures  which  are  most  important  for  the  nurse  to  recognize 
are  those  formed  with  three  borders  of  the  parietal  bones.  The 
two  sagittal  (or  superior)  borders,  uniting  with  each  other,  form 
the  sagittal  suture;  the  frontal  borders,  uniting  with  the  frontal 
bone,  form  the  coronal  suture,  while  the  occipital  borders,  uniting 
with  the  occipital  bone,  form  the  lambdoid  suture. 

BONES  OF  THE  FACE,  14. 

Nasal ' 2  Palate. .    2 

Lacrimal 2  Inferior  turbinated. ...   2 

Zygomatic. 2  Vomer i 

Superior  maxillary. . .    2  Inferior    maxillary,    or 

united,  form  the  maxilla.  mandible i 

Nasal  bones  {os  nasale,  sing.). — Right  and  left.  (Fig.  11.) 
They  are  fiat  in  structure  and  form  the  bridge  of  the  nose,  being 
joined  to  each  other  in  the  median  line  of  the  face  and  to  the  frontal 
bone  above. 


BONES    OF    THE    FACE. 


21 


Lacrimal  bones  (os  lacrimale,  sing.). — Right  and  left;  small 
and  thin,  situated  in  the  walls  of  the  orbits,  just  under  the  ex- 
tremity of  the  supraorbital  margin  (Figs,  ii  and  23).  In  this  bone 
is  the  beginning  of  the  canal  in  which  the  lacrimal  duct  runs  con- 
veying the  tears  into  the  nose,  thus  preventing  them  from  over- 
flowing the  eyelids  and  running  down  the  cheek. 

Zygomatic  bones  {os  zygomaticum,  sing.). — ^Forming  the  promi- 
nences of  the  cheek  (Fig.  11).  They  are  especially  noticeable 
in  certain  races,  as  the  Chinese,  for  example,  who  have  high  "cheek 
bones." 

Maxilla  (or  upper  jaw-bone). — Situated  in  the  front  of  the 
face,  and  composed  of  the  two  superior  maxillary  bones  joined 


Infraorbital  foramen 


Articulates  with  zygo- 
matic bone 
Posterior  dental  canals 


Canine  eminence 


'^jff Tuberosity 


Fig.  14. — Tile  Maxilla. —  (Alorris.) 

together  below  the  nostrils.  It  supports  the  cheeks,  helps  to  form 
the  nose  and  also  the  floor  of  the  orbits.  It  consists  of  a  body  and 
several  processes. 

The  body  is  hollow,  the  space  being  called  the  maxillary  sinus 
or  antrum  of  Highmore  which  opens  into  the  side  of  the  nasal 
cavity.  In  the  lower  border  of  the  body  the  teeth  are  imbedded, 
the  sockets  of  the  large  teeth  being  in  the  floor  of  the  antrum, 
which  explains  how  a  diseased  tooth  may  lead  to  antrum  trouble. 

The  foramen  on  the  surface  of  the  body  just  below  the  orbit  is  called  the 
infraorbital  foramen.  It  is  on  a  line  with  the  supraorbital  foramen  of  the 
frontal  bone  already  mentioned. 

Processes. — The  frontal  process  extends  upward  along  the 
side  of  the  nasal  bone  to  join  the  frontal.     The  palate  process 


22 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


is  in  the  roof  of  the  mouth,  the  bony  part  of  the  roof  being  called 
the  hard  palate.  The  alveolar  process  (or  alveolus)  is  the  thick 
border  of  bone  in  which  the  upper  teeth  are  fixed.  This  process 
is  very  spongy  and  is  sometimes  broken  in  extracting  a  tooth. 
The  zygomatic  process  joins  the  zygomatic  bone  to  form  the 
prominence  of  the  cheek. 


Foramina  and  in- 
cisive suture 


-    Palate  process 


1  Palatine  foramina 
J  in  a  palate  bone 


.  Fig.  15. — The  Hard  Palate,  or  Roof  or  the  Mouth. — (Morris.) 

Palate  bones  {os  palatinum,  sing.). — Right  and  left;  shaped  like 
the  capital  letter  L,  and  placed  behind  the  maxilla.  The  upright 
portion  is  in  the  side  of  the  nose  at  the  back;  the  horizontal 
portion  lies  in  the  floor  of  the  nose,  being  at  the  same  time  in  the 
roof  of  the  mouth,  and  thus  completing  the  hard  palate  (Figs.  20 
and  24). 

Inferior  turbinated  bones  {concha  nasalis  inferior,  sing.). — 
Right  and  left;  situated  in  the  right  and  left  walls  of  the  nasal 
cavity  below  the  superior  and  middle  turbinated  bones  which 
belong  to  the  ethmoid  (Fig,  24) .  Each  is  composed  of  a  thin  plate 
of  spongy  tissue,  having  one  edge  rolled  under  like  a  shell  {concha); 
they  extend  from  front  to  back  on  the  lateral  wall  of  the  cavity. 

Clinical  note. — Hypertrophy  (or  overgrowth)  of  the  inferior 
turbinated  bone  is  a  frequent  cause  of  obstruction  to  proper 
breathing. 

Vomer. — A  thin  bone  resembling  a  plowshare  in  shape,  joined 
above  with  the  vertical  plate  of  the  ethmoid,  and  below  with  the 
maxilla,  thus  forming  the  lower  part  of  the  septum  of  the  nose.     It 


BONES    OF    THE    FACE. 


23 


is  this  part  of  the  septum  which  is  sometimes  bent  to  one  side,  or 
"deflected,"  and  it  often  presents  a  ''spur"  on  one  of  its  surfaces. 
(The  vertical  plate  of  the  ethmoid  and  the  vomer  together  form  the 
bany  septum  Fig.  25.) 


Articulates  with 
ethmoid 


Groove  for  nerve 


Articulates  with 
hard  palate 


Ala 

Posterior  border 


Fig.  16. — The  Vomer. — (Morris.) 

Mandible  (inferior  maxillary,  or  lower  jaw-bone,  mandibula). — 
The  only  movable  bone  in  the  skull.  It  consists  of  a  body  having 
on  either  side  a  ramus  (or  branch)  which  is  attached  by  ligaments 
to  the  temporal  bone. 

The  body  is  the  lower  portion,  shaped  much  like  a  horseshoe, 
with  a  thickened  border  (the  alveolus)  which  bears  the  lower 
teeth. 


Fig.  17. — The  Mandible. 
I,  Body  of  bone;  2,  ramus;  3,  symphysis;  4,  incisive  fossa;  5,  mental  foramen;  7, 
depression  for  passage  of  facial  artery;  8,  angle  of  jaw;  10,  coronoid  process;  11,  con- 
dyle; 12,  sigmoid  notch;  13,  alveolar  border;  a,  incisors;  b,  bicuspids;  c,  canines;  m, 
molars. — (Gould's  Dictionary.) 

On  each  side  is  an  opening  called  the  mental  foramen,  which  is  in  a  line  with 
the  infraorbital  and  supraorbital  foramina,  already  mentioned. 

Each  of  these  three  openings  transmits  an  important  nerve,  artery,  and 
vein,  bearing  the  same  name  as  the  foramen.     See  Surgical  note,  p.  258. 

The  ramus  extends  upward  from  the  body,  and  ends  in  two 
processes,  one  of  which  is  the  condyle;  it  is  this  condyle  which 
articulates  with  the  temporal  bone  to  form  the  temporo-maxillary 
joint. 


H 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


Clinical  note. — Dislocation  of  this  joint  easily  occurs  if  the 
mouth  is  opened  too  widely. 

The  angle  of  the  jaw  or  mandible,  is  the  posterior  extremity  of  the  lower 
border.  The  prominence  of  the  angle  differs  in  different  people  and  at 
different  ages. 

ARTICULATIONS  OF  THE  FACE. 

The  bones  of  the  face  are  all  irregular,  and  many  of  them  are 
very  frail.  They  are  fixed  by  sutures  with  one  exception — that 
of  the  mandible  which  moves  freely.  (For  description  of  a  movable 
joint,  see  page  14.) 

The  Mandibular  Joint. 

The  mandibular  joint  is  a  hinge-joint,  and  the  only  movable 
joint  in  the  skull.     The  action  may  be  felt  in  front  of  the  ear. 

The  bony  surfaces  are  the  condyle  of  the  mandible  and  the 
mandibular  fossa  of  the  temporal  bone.     They  are  covered  with 


Capsule 


Fig.  18. — Mandibular  Joint. — (After  Morris.) 

cartilage  and  connected  by  ligaments  forming  a  capsule,  which  is 
sufficiently  loose  to  allow  the  condyle  to  glide  freely  in  the  fossa, 
back  and  forth  or  sidewise,  as  in  opening  and  closing  the  mouth 
and  masticating  the  food. 

Surgical  notes. — If  the  mouth  be  suddenly  opened  very 
widely,  as  in  hearty  laughing,  dislocation  easily  results — that  is, 
the  condyles  glide  too  far  forward  and  slip  in  front  of  the  fossa. 


THE    SKULL  AS   A    WHOLE. 


25 


making  it  impossible  to  close  the  mouth.  To  correct  this  condition 
(or  "reduce  the  dislocation")  press  the  jaw  forcibly  downivard 
and  backward  with  the  thumbs  placed  upon  the  molar  teeth.  (First 
wrap  the  thumbs  with  a  napkin  to  protect  them,  as  the  mouth 
will  close  suddenly.) 

POINTS  OF  INTEREST  IN  CONNECTION  WITH  THE 
SKULL  AS  A  WHOLE. 

The  Cranium. 

The  cranium  is  a  firm,  strong  case  for  the  brain,  composed 
largely  of  flat  bones,  the  layers  of  these  fiat  bones  being  called  the 
tables  of  the  skull.  The  innermost  table  is  very  brittle  and  may 
be  fractured  by  a  blow  which  does  not  break  the  outer  one,  and 
owing  to  this  brittleness  it  is  called  the  vitreous,  or  glassy  layer. 


GLABELLA, 


ANTERIOR    NASAL; 
SPINE 


PROSTHIO 


Fig.  19. — The  Vertex  and  Side  of  the  Skull. — (Gerrish.) 


Observing  the  illustrations,  or  better,  with  the  skull  in  the 
hand,  the  student  may  trace  the  frontal,  two  parietal,  and  occipital 
bones  forming  the  vault  of  the  skull,  or  the  vertex;  and  at  the  sides 
the  squamous  and  mastoid  portions  of  the  temporal  bones  and  the 
tip  of  the  great  wing  of  the  sphenoid. 


26 


ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 


Turning  the  skull  upside  down,  observe  the  base.  In  the 
median  line  at  the  back  is  the  basal  part  of  the  occipital  bone, 
with  the  foramen  magnum  and  the  condyles  on  either  side  of 
it.  In  front  of  that  are  the  &o(/;y  and /»foce55e5  o///^e  sphenoid,  and 
the  roof  of  the  mouth  (or  hard  palate)  bounded  by  the  upper  teeth. 
Tracing  forward  from  the  lateral  part  of  the  occipital  bone  is  the 


20  F"i,-as».- 


Fig.  20. — Base  of  Skull. 
I,  2,  3,  Foramina  and  sutures  in  hard  palate;  4,  post-nasal  spine;  5,  nasal  septum; 
6,  7?  ^;  9)  1°)  iij  12,  pterygoid  processes,  and  markings  on  sphenoid  bone;  13,  zygomatic 
arch;  14,  spheno-occipital  suture;  15,  16,  17,  18,  19,  20,  markings  on  temporal  bone; 
21,  21,  condyles  of  occipital  bone;  22,  basal  portion  of  occipital  bone;  23,  foramen 
magnum;  24,  25,  crest  and  lines  of  occipital  bone. — (Gould's  Dictionary.) 


petrous  portion  of  the  temporal,  with  its  sharp  styloid  process  and 
round  opening  of  the  carotid  canal;  and  in  front  of  the  temporal  is 
the  great  wing  of  the  sphenoid.  The  ethmoid  may  be  seen  through 
the  posterior  nares  where  the  turbinated  bones  (better,  shell-hones) 
are  all  visible. 

Numerous  openings  or  foramina  pierce  the  base  of  the  skull, 
for  vessels  and  nerves.     The  jugular  foramen  is  just  back  of  the 


THE    FACE. 


27 


carotid  canal;  through  it  the  jugular  vein  leaves  the  skull  to  pass 
downward  in  the  neck.  The  interior  surfaces  of  all  cranial  bones 
show  depressions  for  the  convolutions  of  the  brain. 

The  Face. 

(See  Figs.  19,  23.) 

Beginning  with  the  forehead,  note  the  two  frontal  eminences, 
and  below  these  the  superciliary  arches  with  the  glabella  between 
them.  Still  lower,  the  supraorbital  arches,  with  the  nasal  notch 
between  them,  to  which  the  nasal  bones  are  attached.  Observe 
the  lacrimal  canal  at  the  medial  side  of  the  orbit  leading  to  the  nasal 


Fig.  21.  —  Skull  of  New-born 
Child,  showing  Frontal  Fontanelle. 
—  (Edgar.) 


Fig.  22. — Occipital  Fontanelle. 
Both  cuts  show  moulding  of  the  head. 
—(Edgar.) 


cavity.  Below  the  orbit,  locate  the  infraorbital  foramen  on  the 
surface  of  the  maxilla  and  the  mental  foramen  on  the  body  of  the 
mandible. 

Remember  that  these  three  foramina  transmit  three  very  sensitive  nerves, 
as  follows:  The  supraorbital  nerve  for  the  forehead,  the  infraorbital  nerve  for 
the  cheek,  and  the  menial  nerve  for  the  lower  lip  and  chin.  (Blood-vessels  bearing 
the  same  names  accompany  these  nerves.) 

The  prominences  at  the  sides  of  the  cheeks  are  made  by  the 
zygomatic  bones.  The  openings  of  the  nasal  cavity  are  the  anterior 
nares,  within  which  may  be  seen  the  septum,  and  the  middle  and 
inferior  turbinated  bones  (shell  bones). 


28 


ANATOMY   AND   PHYSIOLOGY    FOR    NURSES. 


The  Skull  at  Birth. 

The  bones  are  only  partially  developed,  a  considerable  space 
between  them  being  occupied  by  membrane  (in  some  places,  carti- 
lage), and  the  frontal  bone  is  in  two  pieces. 

Fontanelles. — The  parietal  and  frmital  bones  are  incomplete 
at  the  angles  where  their  sutures  meet,  leaving  a  diamond-shaped 
space  above  the  forehead  where  there  is  only  membrane,  and  which 
is  called  the  anterior  or  frontal  fontanelle.  The  parietal  and  occipital 
bones  are  also  lacking  where  their  sutures  meet,  leaving  a  triangular 
soft  spot  called  the  posterior  or  occipital  fontanelle,  which  is  much 
smaller.  These  fontanelles  are  closed  as  the  bones  develop;  the 
occipital  in  a  few  months,  the  frontal  before  the  end  of  the  second 
year. 

Obstetric  note. — Owing  to  the  fact  that  the  bones  are  not 
firmly  jointed,  they  can  be  made  to  overlap  and  thus  adapt  the 
shape  of  the  child's  head  to  the  passage  which  it  must  traverse 
during  birth.  This  is  called  the  moulding  of  the  head  (Figs.  21 
and  22). 


Superciliary 
ridge 

Glabella 


Fig.  23. — The  Orbit. — (After  Morris.) 

FOSS.^  OF  THE  SKULL. 

The  four  large  fossae  of  the  exterior  of  the  skull  are  the  temporal, 
infratemporal,  orbital,  and  nasal. 

The  temporal  fossa  (fossa  temporalis). — The  thinnest  part 
of  the  skull  (Fig.  19).  It  is  bounded  by  the  temporal  ridge  and 
the  zygomatic  arch,  occupied  by  the  temporal  muscle,  and  covered 


FOSSiE    OF    THE    SKULL. 


29 


by  a  strong  membrane,  called  the  temporal  fascia,  through  which 
the  motion  of  the  muscle  may  be  felt. 

Infratemporal  (or  zygomatic)  fossa. — At  the  side  of  the  skull 
below  the  temporal  fossa,  from  which  it  is  separated  by  the  zygo- 
matic arch  (Fig.  19).  It  is  covered  by  the  ramus  of  the  mandible, 
and  occupied  by  two  of  the  muscles  of  viastication,  and  also  by  a 
number  of  important  arteries,  veins,  and  nerves. 


Concha  superior 
Sphtnoidxl  binus 


Superior  J 
meatus  I  ^ 


Inferior  meatus  — 


Probe  in 
nasal  canal 


Fig.  24. — Lateral  Wall  of  Nasal  Fossa  or  Cavity. — (Morris.) 


Orbital  fossa  (or  orbit). — Containing  the  eye.  It  is  shaped 
like  a  pyramid,  the  apex  being  at  the  back  of  the  fossa.  The 
large  opening  on  the  face  is  bounded  by  the  margins  of  the  orbit, 
having  the  frontal  bone  above,  the  maxilla  below,  and  the  zygo- 
matic bone  on  the  lateral  side. 

The  orbital  plate  of  tlie  frontal  bone  is  in  the  roof  of  the  orbit,  and  the 
orbital  plate  of  the  maxilla  in  the  Jloor.  The  lacrimal  and  ethmoid  bones  are 
in  the  medial  wall ,  the  sphenoid  and  zygomatic  bones  in  the  lateral  wall. 


3° 


ANATOMY  AND   PHYSIOLOGY   FOR    NURSES. 


The  lacrimal  canal  begins  in  the  lacrimal  bone  and  runs  down 
into  the  nose.  The  optic  foramen,  for  the  optic  nerve,  is  at  the 
apex  of  the  fossa. 

Nasal  fossa. — i?oo/ formed  by  nasal  and  ethmoid  hones;  Jio or 
by  maxillary  and  palate  bones;  lateral  wall  by  nasal,  ethmoid, 
maxillary,  and  palate  bones;  septum  by  ethmoid  and  vomer  (Fig.  24). 

The  openings  on  the  face,  or  anterior  nares,  are  bounded  by  the 
maxillary  and  nasal  bones,  and  separated  by  the  vomer.  The 
posterior  nares  are  bounded  by  the  sphenoid  and  palate  bones, 
separated  by  the  vomer,  and  open  into  the  throat.  Turbinated 
bones  are  seen  on  the    lateral  walls  of  the  fossae. 


Fig.  25. — The  Bony  Septum. 
Body  of  sphenoid  immediately  behind  it. 
—  (Morris.) 


Fig.  26. — Hyoid  Bone,  Anterior 
Aspect. 
1,1,  Anterior  or  convex  surface  of 
body;  2,  2,  greater  cornua;  3,  3,  junc- 
tion of  greater  cornua  with  body;  4, 
lesser  cornua. — (Gould's  Dictionary.) 


Each  nasal  fossa  communicates  with  four  sinuses:  the  sphenoid,  ethmoid, 
frontal,  and  maxillary.  The  sphenoid  sinus  opens  into  the  upper  and  back 
part;  the  ethmoid,  frontal,  and  maxillary  (or  antrum  of  Highmore)  open  at  the 
side,  lower  down.     The  lacrimal  canal  also  opens  at  the  side  near  the  floor. 

The  nasal  fossae  are  lined  with  mucous  membrane  (the 
Schneiderian  membrane)  which  is  continued  into  all  of  the  sinuses 
and  the  pharynx. 

Clinical  note. — Inflammation  of  this  membrane  may  extend  into 
any  of  the  sinuses,  causing  sinusitis.  If  this  occurs  in  the  frontal 
region,  a  dull  pain  is  felt  over  the  eyes;  if  in  the  ethmoid  region,  a 
pain  at  the  side  of  the  nose  and  a  change  in  the  sound  of  the  voice 


BONES    OF    THE    NECK.  3I 

{nasal  tone)  are  noted.     The  inflammation  frequently  extends  into 
the  antrum  of  Highmore. 

The  sense  of  smell  resides  in  the  upper  part  of  the  nose,  the 
olfactory  nerves  coming  down  through  the  sieve-Hke  plate  of  the 
ethmoid  bone  in  the  roof  of  the  fossa. 

BONES  OF  THE  NECK. 

Hyoid,   {os  hyoides);  seven  cervical  vertebrcE. 

The  hyoid  bone,  or  os  hyoides. — Shaped  like  the  letter  U, 
situated  in  front  of  neck,  about  on  a  level  with  the  chin,  and  sus- 
pended by  ligaments  and  muscles  from  the  styloid  process  of  the 
temporal  bone.  The  hyoid  is  not  articulated  to  any  other  bone. 
It  consists  of  a  body  and  four  cornua  (or  horns),  and  is  designed 
to  give  attachment  to  the  muscles  of  the  tongue,  and  to  others  which 
connect  it  to  the  mandible  above  and  sternum  and  clavicle  below. 

Seven  cervical  vertebrae. — The  seven  cervical  vertebrae  and 
their  articulations  will  be  described  with  the  spinal  column. 

THE  TEETH. 

A  tooth  is  composed  of  dentine  or  tooth-bone,  and  consists 
briefly  of  a  crown,  a  neck,  and  a  root. 

The  crown  is  the  exposed  portion  and  is  covered  with  hard 
white  enamel.     The  root  (connected  with  the  crown  by  the  neck) 


Neck 
Cingulum 


Fig.  27. — A  Molar  Tooth  in  Section  and  a  Canine  Tooth. — (Morris.) 

is  concealed  in  the  socket  of  the  jaw  and  is  covered  with  cement. 
The  shape  of  the  tooth  varies  from  that  of  the  flat  incisor  or  cutting 
tooth,  to  the  broad  one  for  crushing  and  grinding. 

The  incisors  are  the  front  teeth,  four  in  number  in  each  jaw. 
They  arc  used  for  biting  and  cutting  the  food. 

The  cuspids  (pointed)  or  canine  teeth  are  situated  next  to  the 
incisors;  they  also  bite. 


32  ANATOMY  AND    PHYSIOLOGY   FOR    NURSES. 

The  bicuspids  (two-pointed)  or  pre-molars,  and  the  molars  are 
for  purposes  of  mastication. 

The  shapes  of  all  are  shown  in  the  illustrations. 

The  teeth  are  hollow  and  contain  tooth-pulp.  This  consists  of 
a  delicate  meshwork  of  vessels  and  nerves  entering  at  the  point  of 
the  root. 

The  upper  teeth  are  imbedded  in  the  alveolus  of  the  maxilla,  or 
upper  jaw;  the  lower  teeth  in  the  alveolus  of  the  mandible,  or  lower 
jaw. 

Dentition :  the  Eruption  of  the  Teeth. 

The  teeth  make  their  appearance  in  two  sets,  called  temporary 
and  permanent. 


k 

ilk  \§        1  MJlT^   «« 

f 

Fig.  28. — The  Tempoeary  Teeth. 
The  rudiments  of  the  permanent  teeth  are  seen  enclosed  in  the  bones. — (Gorgas.) 

The  temporary  teeth  are  twenty  in  number;  their  eruption  or 
"cutting"  usually  begins  at  about  the  seventh  month  and  proceeds 
in  following  order: 

Two  lower  central  incisors at    7  months. 

Two  upper  central  incisors at    8  to  10  months. 

Two  upper  lateral  incisors at    9  to  12  months. 

Two  lower  lateral  incisors    at  12  to  15  months. 

Four  first  molars,  i  right,  i  left  in  each  jaw at  12  to  15  months. 

Four  canines,  i  right,  i  left  in  each  jaw    at  16  to  22  months. 

Four  second  molars,  i  right,  i  left  in  each  jaw    .  .  at  24  to  30  months. 
Twenty  teeth  in  the  temporary  set  at  two  and  one-half  years  of  age. 


THE    TEETH. 


33 


Thus,  at  one  year  of  age  the  average  child  will  have  six  teeth; 
at  two  years,  sixteen;  and  the  full  number  before  it  is  three  years 
old.  Many  exceptions  occur,  for  example:  the  dentition  of  artifici- 
ally fed  children  may  be  delayed;  and  it  is  oftenest  late  in  children 
affected  by   rachitis  or  "rickets." 

The  upper  canines  are  known  in  the  nursery  as  "eye-teeth";  the  lower 
canines  as  "stomach  teeth." 

Clinical  points. — "Teething"  or  "cutting"  of  the  temporary 
set  occurs  while  the  digestive  tract  is  still  in  process  of  develop- 
ment and  very  easily  disturbed;  therefore  special  care  should  be 


Premolar 


Molars 


Wisdom  tooth 


Fig.  29. — The  Tp:eth  of  an  Adult. — (Morris'  Anatomy.) 


given  to  the  child's  diet  both  as  to  quality  and  c^uantity.  Likewise, 
the  always  delicate  nervous  system  is  at  this  time  most  easily  irritated 
and  excitement  and  fatigue  should  be  avoided.  These  two  points 
are  equally  important. 

Meanwhile  the  permanent  teeth  arc  forming  (Fig.  29).  They 
gradually  push  toward  the  surface,  cutting  ofi  the  blood  supply  to 
the  temporary  teeth  which  become  loose  and  fall  out. 

The  permanent  teeth  are  thirty-two  in  number.     At  the  age 
of  six  years  the  first  permanent  molar  ("six-year  molar")  should 
appear;  the  others  follow  in  order  somewhat  like  the  following: 
3 


34  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

Four  first  molars,  i  right,  i  left,  in  each  jaw at    6  years. 

Eight  incisors,  2  central,  2  lateral,  in  each  jaw    ...  at    7  to    8  years. 

Eight  bicuspids,  2  right,  2  left,  in  each  jaw at    8  to  10  years. 

Four  canines,  i  right,  i  left,  in  each  jaw at  12' to  14  years. 

Four  second  molars,  i  right,  i  left,  in  each  jaw  ..  .at  12  to  15  years. 

■      Four  third  molars,  i  right,  i  left,  in  each  jaw at  17  to  25  years. 

(The  third  molars  are  called  "wisdom  teeth.") 

Thirty-two  teeth  in  permanent  set  at  twenty-five  years  of  age. 

Clinical  notes. — Caries,  or  decay  of  teeth,  is  due  to  bacterial 
action.  This  is  favored  by  accumulation  of  particles  of  food,  the 
warmth  and  moisture  of  the  mouth  furnishing  perfect  conditions  for 
the  development  of  bacteria.  Careful  cleansing  with  brush  or  dental 
floss,  or  both,  will  prevent  this  and  thus  aid  in  preserving  the  teeth. 
Care  is  important  in  the  use  of  brush  or  floss  or  toothpick,  not  only 
that  the  removal  of  injurious  particles  may  be  well  done  but  in  order 
to  avoid  wounding  the  mucous  membrane  which  covers  the  gums, 
thus  exposing  them  to  bacterial   irritation. 

Recession  of  the  Gums. — Any  irritation  (as  by  bacteria)  of  the 
gums  may  be  followed  by  their  recession,  which  exposes  the  dentine 
where  it  is  not  protected  by  enamel. 

Sudden  changes  of  temperature,  as  from  hot  to  cold  liquids,  is 
injurious  to  the  enamel.  Acids  as  ordinarily  taken  in  food,  have  no 
special  action  upon  the  teeth  but  sweets  may  do  harm  by  their 
fermentation  in  a  mouth  where  teeth  are  not  kept  clean. 


CHAPTER  III. 

BONES  AND  ARTICULATIONS  OF  THE 
SPINAL  COLUMN  AND  TRUNK. 

The  bones  •  of  the  spinal  column  are 
twenty-six  in  number.  They  are  irregular 
and  are  arranged  as  follows,  from  above 
downward : 


24  separate  vertebras 


I  sacrum. 
I  coccyx. 


r     7  cervical  in  the  neck. 

I   12  thoracic  in  the  back. 

[     5  lumbar  in  the  loins. 

1 

\  in  the  pelvis. 

J 


A  vertebra  consists  of  a  body  and  an 
arch,  joined  together  to  form  a  ring  of 
bone  with  a  space  enclosed  called  the 
vertebral  foramen,  which  is  occupied  by  the 
spinal  cord.  The  bodies  are  composed  of 
spongy  bone,  placed  one  above  the  other  and 
held  together  by  discs  of  fibrocartilage  be- 
tween them.  In  this  way  the  solid  and 
flexible  portion  of  the  spine  is  constructed. 

The  arch  consists  of  two  roots  next  to  the 
body,  and  two  lamince  which  meet  at  the 
back.  There  are  seven  processes  on  the 
arch  of  each  vertebra, — four  articular  (two 
to  form  joints  with  the  bone  above,  two 
for  the  bone  below);  two  transverse  (pro- 
jecting from  the  sides),  and  one  spinous 
which  projects  backward.  The  row  of 
spinous  processes  is  felt  by  passing  the  fmger 
down  the  back  in  the  median  line;  that  of 
the  seventh  vertebra  is  easily  seen,  and  this 
bone  is  called  the  vertebra  prominens. 

35 


Fig.  30. — Vertebral 
Column,  Lateral  Aspect. 

1-7,  Cervical  vertebrae; 
8-19,  dorsal  vertebrae;  20- 
24,  lumbar  vertebrae;  A,  A, 
spinous  processes;  B,  B, 
articular  facets  of  trans- 
verse processes  of  first  ten 
dorsal  vertebrae;  C,  auricu- 
lar surface  of  sacrum;  D, 
I),  foramina  in  transverse 
processes  of  cervical  verte- 
brae.—  (Gould's  Illus.  Dic- 
tionary.) 


36  anatomy  and  physiology  for  nurses. 

Points  of  Special  Interest, 

The  cervical  vertebras  present  a  foramen  at  the  base  of  the  transverse 
process,  the  transverse  foramen,  through  which  an  artery  runs  to  the  brain, 
entering  the  skull  through  the  foramen  magnum.  (There  are  no  transverse 
foramina  in  the  dorsal  or  lumbar  regions.)  Their  spinous  processes  are  cleft, 
or  bifid. 


Transverse  foramen 
Transverse  process 

Articular  process 


Lamina 


Spinous  process 


Pedicle 


Fig.  31. — Cervical  Vertebea,  Showing  Bifid  Spinous  Process. — (Morris.) 


Fig.  32. — Atlas,  Superior  Surface. 
I,  Tubercle  of  anterior  arch;  2, 
articular  facet  for  odontoid  process 
of  axis;  3,  posterior  arch  and  posterior 
tubercle;  4,  groove  for  vertebral  artery 
and  first  cervical  nerve;  5,  transverse 
process;  6,  transverse  foramen;  7, 
superior  articular  process;  8,  tubercle 
for  attachment  of  transverse  ligament. 
— (Gould's  Dictionary.) 


Fig.  t,t,. — Axis,  Posterosu- 
perior  View. 
I,  Posterior  surface  of 
body;  2,  odontoid  process;  3, 
3,  superior  articular  proc- 
esses; 4,  4,  inferior  articular 
processes;  5,  5,  transverse 
processes;  6,  spinous  process. 
— (Gould's  Dictionary.) 


The  first  is  called  the  atlas.  It  is  a  mere  ring  but  has  the  usual  number  of 
processes  (Fig.  32).  The  atlas  is  so  named  because  it  bears  the  weight  of  the 
skull  (as  Atlas,  the  fabled  giant,  bore  the  globe  upon  his  shoulders). 

The  second  is  the  axis.  A  strong  process  projects  upward  from  its  body 
forming  a  pivot  for  the  ring-like  atlas  to  revolve  around.  The  pivot  is  called  the 
tooth  (or  odontoid  process)  and  is  held  in  its  place  in  the  front  part  of  the  ring  of 


BONES    OF    THE    SPINAL    COLUMN. 


37 


the  atlas  (Fig.  32)  by  a  strong  ligament,  which  prevents  it  from  pressing  upon 
the  spinal  cord. 

The  thoracic  vertebrae  are  peculiar,  in  that  their  bodies  present 
marks  for  the  head  of  ribs;  also,  they  have  long  transverse  and 
spinous  processes. 


Fig.  34. — A  Thoracic  Vertebra,  showing  marks  for  Head  of  Rib. — (Morris.) 

The  lumbar  vertebrae  are  the  largest  and  strongest  in  the  column, 
the  bodies  being  conspicuously  thicker  than  in  the  other  regions, 
especially  in  the  case  of  the  fifth. 

There  are  various  other  modifications  of  bones  in  the  three  regions — 
cervical,  dorsal,  and  lumbar — which  need  not  be  mentioned  here. 


Fig.  35. — A  Lumbar  Vertebra  in  Section  to  show  the  Pressure 
Curves. — (Morris.) 

Sacrum. — An  irregular  bone  formed  by  the  consolidation  of 
five  incomplete  vertebrae,  and  joined  to  the  last  lumbar.  Its  general 
shape  is  that  of  a  curved  wedge;  it  is  placed  with  the  base 
upward,  and  the  concavity  forward,  forming  the  ^^  hollow  of  the  sac- 
rum." A  canal  extends  from  the  base  to  the  apex,  called  the  sacral 
canal,  which  is  a  continuation  of  the  spinal  (or  neural)  canal. 

There  are  two  sets  of  short  canals,  running  from  front  to  back 
through  the  sacrum.     Seen  from  the  front  they  present  the  an- 


38 


ANATOMY  AND   PHYSIOLOGY    FOR    NURSES. 


ierior  sacral  foramina;  seen  from  the  back,  the  posterior  sacral  for- 
amina (for  the  passage  of  nerves).  The  angle  formed  by  the  sacrum 
and  the  fifth  lumbar  vertebra  projects  sharply  forward  and  is  called 
the  promontory. 

Coccyx. — The  terminal  bone  of  the  spinal  column,  and  formed 
of  four  very  rudimentary  vertebrae.  The  base  is  joined  to  the 
sacrum;  the  apex  is  directed  downward  and  forward. 


Fig.  36. — Sacrum,  Anterior  Aspect. 
I,  I,  I,  I,  Bodies  of  sacral  vertebrae  with  trans- 
verse lines  of  union;  2,  2,  2,  2,  anterior  sacral  fora- 
mina; 3,  base;  4,  auricular  surface  of  lateral  aspect; 
5,  its  inferior  portion;  6,  articular  surface  of  base; 
7,  notch  for  formation  of  last  lumbar  intervertebral 
foramen,  8,  superior  articular  process  of  first  sacral 
vertebra;  9,  apex  of  sacrum;  10,  cornu;  11,  notch  for 
transmission  of  fifth  sacral  nerve. — (Gould's  Illus- 
trated Dictionary.) 


Fig.    37. — Coccyx,   Ante- 
rior Aspect. 
I,  Base;  2,  2,  cornua;  3 
second  coccygeal  vertebra; 

4,  third  coccygeal  vertebra; 

5,  fourth  coccygeal  vertebra; 

6,  fifth  coccygeal  vertebra. 
— (Gould's  Illustrated  Dic- 
tionary.) 


THE  ARTICULATIONS  OF  THE   SPINAL  COLUMN. 

The  bodies  of  the  vertebrae  are  connected  by  discs  of  fihro- 
cartilage  which  are  placed  between  them.  They  serve  not  only 
to  connect  the  vertebrae  but  to  give  flexibility  to  the  column,  so 
that  it  may  bend  in  any  direction,  and  they  also  make  it  elastic. 
The  bodies  are  further  connected  by  fibrous  bands  on  their  anterior 
and  posterior  surfaces.     (Slightly  movable  or  yielding  joints.) 

The  arches  are  connected  by  broad  thin  ligaments  between  the 
laminae,  thus  completing  the  spinal  or  neural  canal,  which  contains 
the  spinal  cord.  (These  ligaments  are  an  exception  to  the  rule, 
in  that  they  are  elastic;  they  are  called  the  ligamenta  Jiava.)  The 
articular  processes  are  covered  with  cartilage  and  enclosed  by 
capsules  which  are  lined  with  synovial  membrane,  forming  true 
movable  joints.     These  are  gliding  joints.     (Arthrodia.) 


ARTICULATIONS    OF    THE    SPINAL    COLUMN. 


39 


K 


The  only  independent  movements  of  the  head  are  provided  for 
by  the  arrangement  of  the  atlas  and  axis.  The  cup-like  articular 
processes  of  the  atlas  receive  the  condyles  of  the  occipital  bone  to 
allow  the  nodding  motion  of  the  head.  The  occipital  bone  is  held 
to  the  atlas  by  ligaments,  and  rotation  of  the  atlas  around  the  tooth  of 
the  axis  turns  the  head  also,  from  side  to  side. 

The  ligamentum  nuchae  is  a  name  given  to  a  thick  elastic  band 
(not  a  true  ligament)  which  stretches  from  the 
occipital  protuberance  to  the  seventh  spinous 
process.  It  helps  to  sustain  the  weight  of 
the  head  while  bending  forward,  and  is 
particularly  well  developed  in  the  larger 
grazing   animals. 

From  the  seventh  cervical  down  to  the  sacrum  a 
supraspinous  ligament  is  stretched,  attached  to  all  the 
spinous  processes. 

The  movements  of  the  spinal  column  are 
flexion,  extension,  lateral  flexion,  and 
rotation.  Motion  is  freest  in  the  cervical 
region,  and  most  restricted  in  the  dorsal. 

Clinical  note. — The  limited  motion  be- 
tween neighboring  bones  becomes  a  wide 
range  in  the  column  as  a  whole  and  may  be 
increased  by  frequent  and  judicious  exercises. 

THE  SPINE  AND  THE  SPINAL 
CURVES. 


The  length  of  the  spine  is  about  27  inches. 
The  solid  portion  is  a  flexible  and  elastic 
column  which  bears  the  weight  of  the  head 
and  its  delicate  organs  without  giving  them 
the  full  force  of  the  jar  caused  by  walking, 
running,  etc.  The  flexibility  of  the  column 
allows  the  whole  body  to  move  with  freedom 

and  grace,  while  the  strength  of  the  spine  makes  it  suitable  for  the 
attachment  of  the  extremities.  The  arches,  connected  by  their 
ligaments,   enclose   the   spinal  or   neural   canal,  which  extends 


Fig.  38. — Spine  and 
Spinal  Curves. 


40  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

through  the  sacrum  to  the  base  of  the  coccyx.  Since  the  spinal  canal 
contains  the  spinal  cord  there  must  be  places  of  exit  for  the  spinal 
nerves;  these  are  found  in  the  intervertebral  foramina  between  the 
roots  of  the  arches. 

The  spine  has  four  curves:  cervical,  thoracic,  lumbar,  and 
sacral. 

■  The  cervical  and  lumbar  curves  are  concave  posteriorly,  as  is 
seen  to  a  slight  degree  in  the  back  of  the  neck,  and  more  plainly 
in  the  so-called  ''small  of  the  back";  while  the  thoracic  and  sacral 
curves  are  concave  anteriorly,  to  accommodate  the  organs  in  the 
thorax  and  pelvis. 

These  curves  are  caused  by  variations  in  the  thickness  of  the  bodies  and 
cartilage  discs.  For  example,  the  thoracic  bodies  are  slightly  thicker  at  the 
back,  while  the  lumbar  bodies  are  thicker  in  front. 

A  lateral  curve  usually  exists  in  the  upper  thoracic  region,  but 
this  may  be  called  accidental,  as  it  is  explained  by  the  excessive 
use  of  one  or  the  other  arm. 


THE  TRUNK. 
Includes  the  Thorax,  Abdomen  and  Pelvis. 

BONES  OF  THE  THORAX. 

Sternum i 

Ribs  (costae) , 24 

Thoracic  vertebrae .....' 12 

Sternum  or  breast-bone. — Placed  in  the  front  of  the  thorax. 
It  is  about  6  inches  long,  flat  in  shape  and  structure,  and  its  two 
surfaces  are  called  anterior  and  posterior.  It  has  three  divisions, 
the  manubrium,  the  body,  and  the  xiphoid  appendix  (Fig.  39). 

The  upper  border  of  the  sternum  is  notched — the  sternal  (or 
jugular)  notch;  the  lateral  borders  give  attachment  from  above 
downward  to  the  clavicle  and  the  cartilages  of  the  first  seven  ribs. 
The  xiphoid  appendix  is  the  lowest  portion  of  the  bone  and  gives 
attachment  to  some  of  the  muscles  of  the  abdomen.  It  remains 
cartilaginous  until  middle  life. 

Ribs  (costae). — Twelve  in  each  side  of  the  thorax,  forming  a 
series  of  movable  elastic  arches.     They  consist  of  a  bony  portion 


BONES    OF    THE    THORAX. 


41 


(the  costal  hmie)  and  a  flexible  portion  (the  costal  cartilage).     They 
are  flat  in  structure,  curved  in  shape. 

The  posterior  or  vertebral  extremity  is  the  head,  next  to  the  head 
is  the  iieck,  and  the  remaining  bony  portion  is  the  shaft.  The 
inner  surface  of  the  shaft  is  marked  by  a  groove  at  its  lower  border 
(the  costal  groove)  in  which  the  intercostal  nerves  and  vessels  run, 
being  thus  protected  from  external  injury. 


Fig.  39. — The  Thorax. 
I,  2,  Manubrium  and  body  of  sternum;  3,  xiphoid  appendix;  4,  circumference  of 
apex  of  thorax;  5,  circumference  of  base;  6,  fiirst  rib;  7,  second  rib;  8,  8,  third,  fourth, 
fifth,  sixth,  and  seventh  ribs;  9,  eighth,  ninth  and  tenth  ribs,  10,  eleventh  and  twelfth 
ribs;  11,  11,  costal  cartilages. — (Gould's  Dictionary.) 


The  first  seven  are  called  '■'■true  ribs/^  being  connected  in  front 
with  the  sternum  by  their  cartilages.  The  remaining  five  are 
"false  ribs";  the  eighth, ninth  and  tenth  arc  connected  in  front,  each 
to  the  one  above;  the  eleventh  and  twelfth,  arc  not  connected  with 
anything  in  front,  and  arc  called  "floating  ribs." 

Thoracic  vertebrae. — Twelve  in  number;  described  with  the 
bones  of  the  spinal  column. 


42 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


Tubercle 


The  seventh  rib  of  the  left  side,  inferior 
surface. 

The  costal  groove  is  seen,  to  the  borders 
of  which  the  intercostal  muscles  are  at- 
tached, thus  completing  a  channel  for  in- 
tercostal vessels  and  nerve. 

The  tubercle  is  at  the  beginning  of  the 
shaft;  the  articular  surface  marked  a,  is  a 
part  of  the  tubercle. 


Fig.  40. — The  Seventh  Rib. 
a,  articular  surface  for  transverse  process;  b,  neck.— (Morris.) 


ARTICULATIONS    OF    THE    THORAX. 


ARTICULATIONS  OF  THE  THORAX. 


43 


Sternum. — The  three  pieces  {manubrium,  body,  and  xiphoid  ap- 
pendix) are  connected  together  by  fibro-cartilages  and  anterior  and 
posterior  ligaments.  After  middle  life  they  become  united  in  one 
bone. 

Ribs  (costse). — The  costal  cartilages  are  connected  in  front  to  the 
sternum,  or  to  each  other,  as  already  mentioned.  The  heads  arti- 
culate with  the  bodies  of  two  thoracic  vertebrae.  (Exceptions: 
the  first,  eleventh,  and  twelfth  are  each  connected  to  one  body.) 
Where  the  neck  of  the  rib  joins  the  shaft  (marked  by  a  tubercle) 
it  rests  against  the  tip  of  the  transverse  process  of  a  vertebra  behind 


Head  of  rib 


Articular  surface  of 
transverse  process 


Intcr-articular  liga- 
ment 


Fig.  41. — Heads  of  Ribs  Articulating  with  two  Vertebra. — (After  Alorris.) 


it,  which  thus  forms  a  brace  for  it.  All  of  these  joints  are  enclosed 
by  capsules  and  lined  with  synovial  membrane,  providing  for  the 
movements  of  the  ribs  in  breathing,  talking,  etc.     (Figs.  39,  41). 

Vertebrae. — Their  joints  have  been  described. 

By  the  articulation  of  the  ribs  with  the  spine  at  the  back  and 
sternum  in  the  front,  the  bony  thorax  is  completed.  It  is  shaped 
like  a  cone,  flattened  before  and  behind,  and  shortest  in  front 
(the  sternum  reaching  only  as  low  as  the  ninth  dorsal  vertebra). 
The  intervals  between  the  ribs  are  called  the  intercostal  spaces. 

The  elasticity  of  the  ribs  and  cartilages  and  their  gliding  joints, 
give  a  yielding  character  to  the  thoracic  walls  to  accommodate  the 
movements  of  the  lungs  within. 


44  ANATOMY  AND   PHYSIOLOGY   FOR    NURSES. 

BONES  OF  THE  ABDOMEN. 

The  five  lumbar  vertebrae,  already  described. 

BONES  OF  THE  PELVIC  GIRDLE. 

I  Hip  bones 2 

The  bones  are \  Sacrum i 

[  Coccyx I- 

Hip-bone  (os  coxae). — Consisting  of  three  parts  which  are 
entirely  separate  in  the  child.  They  are  the  os  ilium,  the  os  ischii, 
and  the  os  pubis;  they  unite  in  forming  a  cup-shaped  cavity 
called  the  acetabulum,  seen  on  the  lateral  surface  of  the  bone.  The 
acetabulum  is  the  socket  of  the  hip-joint  (Fig.  42). 


Fig.  42. — Hip-bone,  Exterior. — (Morris.) 

The  OS  ilium  is  the  highest  part  of  the  hip-bone  and  has  a 
broad  expanded  portion  called  the  wing  (or  ala).  The  medial 
surface  of  the  wing  is  the  iliac  fossa,  which  is  filled  with  the  iliac 
muscle;  the  lateral  surface  is  crossed  by  three  curved  lines  (called 
the  posterior  gluteal,  the  anterior  gluteal,  and  the  inferior  ghiteal 
lines). 


BONES    OF    THE    PELVIS. 


45 


The  superior  border  is  called  the  crest.  It  can  be  easily  felt,  and 
the  anterior  extremity  is  known  as  the  anterior  superior  iliac  spine, 
more  often  called  the  spine  of  the  ilium. 

The  OS  pubis  is  the  anterior  division  of  the  hip-bone.  It  has  a 
body  and  two  branches,  or  rami.  The  body  joins  the  ilium,  the 
superior  ramus  has  a  short  projection  called  the  spine  of  the  pubes, 
and  the  inferior  ramus  extends  downward  and  backward  to  join 
the  ischium,  thus  forming  the  upper  part  of  the  pubic  arch.  The 
two  pubic  bones  join  each  other  in  the  median  line,  forming  the 
pubic  symphysis  (symphysis  pubis). 


Os  ilium 


Os  pubis 


Fig.  43. — Hip-BOXE,  Interior,  before  Union  of  Parts. — (Morris.) 


The  OS  ischii  (or  the  ischium),  the  lowest  part  of  the  hip-bone, — 
has  a  sharp  spine  projecting  backward,  a  tuberosity  upon  which  the 
trunk  rests  in  the  sitting  position,  and  a  ramus  which  joins  the 
pubic  ramus  to  complete  the  pubic  arch. 

The  ilium,  ischium,  and  pubes  united  form  the  hip-bone  (os 
coxae).  Two  large  notches  are  seen  on  the  posterior  border  of  the 
completed  bone,  separated  by  the  spine  of  the  ischium  and  called 
the  sciatic  notches.  The  upper  one  is  the  greater  and  the  lower 
one  is  the  lesser  sciatic  notch.     In  front  of  the  acetabulum  is  the 


46 


ANATOMY  AND   PHYSIOLOGY    FOR   NURSES. 


obturator  foramen,  the  largest  foramen  in  the  skeleton.  It  is  almost 
entirely  closed  by  the  obturator  membrane,  which  is  composed  of 
white  fibrous  tissue. 

THE  ARTICULATIONS  OF  THE  PELVIS. 

The  two  hip-bones  unite  with  each  other  in  front  at  the  pubic 
symphysis,  but  the  sacrum  is  between  them  in  the  back,  having 
the  coccyx  attached  to  its  apex,  and  thus  the  pelvic  girdle  is  formed, 
usually  called  the  pelvis  (or  basin).  These  joints  have  no  cavity, 
and  are  only  slightly  movable,  or  yielding.  There  is  a  distinct 
disc  of  fibro-cartilage  at  the  pubic  symphysis. 


Greater  sacro- 
sciatic  ligament 


Lesser  sacro-sci- 
atic  ligament 


Tendon  of  biceps  muscle 


Fig.  44. — Greater  and  Lesser  Sacro-sciatic  Ligaments  and  Foramina. — (Morris.) 

Obstetric  note. — The  pubic  symphysis  and  the  sacro-iliac  symphysis 
probably  soften  slightly  during  pregnancy.  The  sacro-coccygeal  joint  has 
limited  motion  until  middle  life  advances,  when  it  may  become  fixed. 

Sacro-sciatic  ligaments  (Fig.  44).— Two  strong  bands  are  stretched 
between  the  sacrum  and  the  ischium.  They  have  no  connection  with  any  joints 
but  are  called  the  greater  and  the  lesser  sacro-sciatic  ligaments.     The  greater 


THE    PELVIC    GIRDLE.  47 

(ligamentum  sacro-tuberosum)  extends  from  the  borders  of  the  sacrum  and 
coccyx  to  the  tuberosity  of  the  ischium;  the  lesser  (ligamentum  sacro-spinosum) 
is  placed  immediately  in  front  of  it,  extending  from  the  sacrum  and  coccyx  to 
the  spine  of  the  ischium.  Thus  are  formed  two  foramina  with  the  lesser  liga- 
ment between  them,  the  one  above  being  called  the  greater  sciatic  foramen, 
and  the  one  below  the  lesser  sciatic  foramen.  (The  sciatic  nerves  pass  through 
the  greater  foramen.) 


Fig.  45. — The  Pelvis. — (Morris.) 

Pouparfs  ligament,  or  the  inguinal  ligament,  may  be  felt  like 
a  tight  cord  stretched  between  the  spine  of  the  ilium  and  the  spine 
of  the  pubis — "from  spine  to  spine." 

The  Pelvis  or  Pelvic-Girdle. 

False  pelvis. — The  upper  part,  between  the  wings  of  the  ilia. 
It  is  broad  and  shallow. 

True  pelvis. — The  lower  part,  bounded  by  the  puhes  in  front,  the 
ischia  at  the  sides,  and  the  sacrum  and  coccyx  at  the  back.  It  is 
deeper  and  narrower. 

The  female  pelvis  has  lighter  bones,  a  wider  pubic  arch,  and 
greater  capacity  than  the  male  pelvis;  the  sacrum  is  less  curved  and 
the  sacral  promontory  less  projecting. 

The  limiting  line  or  boundary  between  the  false  and  the  true 
pelvis   is  a  curved  line  called  the  brim,  and  the  space  included 


48 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


is  the  inlet;  the  lower  openmg  is  the  outlet.  The  inlet  and  the 
outlet  are  also  known  as  the  superior  and  inferior  straits.  The 
measurements  or  diameters  of  these  straits  in  the  female  pelvis  are 
as  follows: 


16 

V_7      7 

P  lAC  ft  E  SAL 

Fig.  46. — The  Pelvis.     Inlet,  or  Superior  Strait. — (Gould's 
Dictionary.) 
I,  Iliac  fossa;  2,  crest  of  ilium;  3,  anterior-superior  spine  of  ilium;  4,  anterior-infe- 
rior spine  of  ilium;  5,  ilio-pectineal  joint;  6,  7,  body  an^  symphysis  of  pubes;  8,  acetabu- 
lum; 9,  tuber  of  ischium;  10,  11,  pubic  arch;  12,  spines  of  ischia;  13,  coccyx;  14,  sacro- 
iliac joint;  15,  is  placed  just  above  the  promontory. 

Inlet  (Edgar's  Obstetrics). 
Antero-posterior 11  cm. 

(Symphysis  to  promontory.) 
Oblique. 12^  cm. 

(Ilio-pectineal  joint  to  sacro-iliac  joint.) 
Transverse 13  J  cm. 

(Widest  part  of  brim.) 

Outlet. 
Antero-posterior 92^12  cm. 

(Symphysis  to  tip  of  coccyx.) 
Transverse 11  cm. 

(Between  tuberosities.) 


THE  DORSAL  AND  VENTRAL  CAVITIES  OF  THE  BODY. 

By  articulation  of  the  bones  of  the  head  and  trunk  a  framework 
is  formed  for  two  cavities,  within  which  are  situated  the  internal 
organs  or  viscera.  (These  delicate  and  important  parts  must  be 
provided  with  surrounding  structures  which  insure  both  their  safety 
and  efficiency.) 

The  cavities  are  called  dorsal  and  ventral,  or  neural  and 
visceral.     Briefly   speaking,    they   may   be   described   as   situated 


THE    DORSAL   AND    VENTRAL    CAVITIES.  49 

posteriorly  and  anteriorly  to  the  solid  part  of  the  spinal  column  or 
bodies  of  the  vertebrae. 

The  spinal  canal  is  a  part  of  the  dorsal  or  neural  cavity  which 
extends  into  the  interior  of  the  skull,  the  bones  of  the  cranium  being 
modified  vertebrae,  and  the  ca\dty  within  them  representing  the 
uppermost  part  of  the  neural  canal. 

The  dorsal  or  neural  cavity  contains  the  brain  and  spinal  cord, 
well  protected  within  iirm,  unyielding  walls. 

The  mouth,  neck,  thorax,  abdomen  and  pelvis  inclose  the  ventral 
or  visceral  cavity,  which  is  in  front  of  the  spinal  column.  The 
bony  walls  are  very  incomplete,  especially  in  the  abdomen.  They 
are  finished  out  by  muscles;  this  arrangement  allows  the  walls  to 
be  flexible  and  yielding  in  character,  thus  securing  to  the  organs  con- 
tained, that  freedom  of  movement  which  is  necessary  to  their  perfect 
action.  The  diaphragm  (page  91)  divides  the  ventral  cavity  into 
two  portions,  upper  and  lower;  the  pelvic  floor  (page  103)  completes 
the  boundary  below. 

The  ventral  cavity  contains  the  organs  of  respiration,  circulation, 
digestion  and  reproduction;  also  the  kidneys  and  bladder,  which  are 
organs  of  elimination. 

Having  studied  the  bones  of  the  dorsal  and  ventral  cavities  or 
those  of  the  head  and  trunk,  we  will  proceed  in  Chapter  IV  to  those 
of  the  extremities. 


CHAPTER  IV. 


BONES  AND  ARTICULATIONS  OF  THE  EXTREMITIES. 

BONES  OF  THE  UPPER  EXTREMITY. 

The  upper  extremity,  as  the  artist  sees  it,  begins  with  the  arm. 
The  anatomist  includes  the  shoulder  as  a  part  of  the  extremity. 
The  bones  are  therefore  as  follows: 


In  the  shoulder. 

In  the  arm 

In  the  forearm. . 


In  the  wrist  or  carpus^ 


In  the  hand. 


I  clavicula 

I  scapula 
humerus  , 

/  radius 

[  ulna 
scaphoid 
semilunar 
cuneiform 
pisiform 


1 • 

I 

1 


ist  row. . . 


2d  row. 


.8 


trapezium 

trapezoid 

OS  magnum 

unciform            J 
J  palm  or  metacarpus  (metacarpal  bones)  5 
[  fingers  or  digits  (phalanges) 14 


32 

*  The  names  of  carpal  bones  are  given  as  follows  in  Spalteholz's  Hand  Atlas: 
ist  row— OS  naviculare  manus.     2nd   row — os  multangulum  majus. 
OS  lunatum.  os  multangulum  minus. 

OS  triquetrum.  os  capitatum. 

OS  pisiforme.  os  hamatum. 

Note. — The  end  of  a  bone  which  is  nearest  to  the  trunk  is  called  the  proximal 
extremity;  the  other  end  is  the  distal  extremity.  The  same  terms  are  applied 
to  surfaces 

The  Shoulder  or  Shoulder-girdle. 

Scapula,  or  shoulder-blade  (Fig.  47).— Placed  a<-  the  upper 
part  of  the  chest,  behind  the  ribs  (from  the  second  to  the  eighth). 
It  is  fiat  and  irregular  in  structure,  and  triangular  in  shape. 

SO 


BONES    OF    THE    UPPER    EXTREMITY. 


SI 


The  margins  are  called  the  superior,  the  vertebral,  and  iheaxillary;  the 
angles,  lateral,  medial,  and  inferior.  The  inferior  angle  and  vertebral  border 
or  margin  usually  project  a  little  backward,  sometimes  very  notably,  making 
the  so-called  "winged  scapula." 

The  anterior  surface  (costal  surface)  is  called  the  subscapular 
fossa,  and  is  filled  with  the  subscapular  muscle.     The  posterior  or 

dorsal  surface  is  crossed  by  a  rough 
ridge  called  the  spine  of  the  scapula 
which  terminates  in  an  important 
process,  the  acromion,  overhanging 
the  shoulder-joint. 

Below  and  in  front  of  the  acromion  is 
the  coracoid  process. 


Fig.  47. — Scapula,  Posteroex- 

TEioiAL  Aspect. 

I,    Supraspinous   fossa;    2,    infra- 

spinous  fossa;  3,  superior  or  coracoid 

border;  4,  coracoid  or  suprascapular 

notch;    5,  axillary   or   lateral  border; 

6,  anterior  angle  and  glenoid  cavity; 

7,  inferior  angle;  8,  rough  impression 
for  long  head  of  triceps;  9,  medial  or 
spinal  or  vertebral  border;  10,  spine; 
ir,  smooth  surface  over  which  tra- 
pezius muscle  glides;  12,  acromion;  13 
base  of  spine;  14,  coracoid  process. — 
(Gould's  Dictionary.) 


Fig.  48. — Clavicle,  Inferior  Aspect. 
I,  Longitudinal  depression  for  insertion 
of  subclavius  muscle;  2,  rough  impression 
for  attachment  of  costoclavicular  ligament; 
3,  3,  for  attachment  of  coraco-clavicular 
ligaments;  4,  4,  posterior  border;  5,  5,  an- 
terior border;  6,  facet  for  articulation  with 
sternum;  7,  facet  for  articulation  with  acro- 
mion.— (Gould's  Dictionar}'.) 


The  lateral  angle  presents  a  shallow  depression  called  the 
glenoid  cavity.     This  cavity  forms  the  socket  of  the  shoulder-joint. 

Clavicula  (or  collar-bone,  Fig.  48.) — Long  in  shape,  but  having 
no  medullary  canal.  It  is  curved  like  an  italic  letter /and  placed 
horizontally  across  the  front  of  the  upper  ribs.  The  inner  extremity 
articulates  with  the  sternum  and  is  therefore  called  the  sternal 
extremity.  The  outer  extremity  articulates  with  the  acromion 
process  of  the  scapula,  and  is    called  the  acromial  extremity. 

Clinical  note. — The  weight  and  curves  are  increased  by  exercise, 
and  both  bones  are  usually  more  developed  in  men  than  in  women. 


52 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


The  clavicula  Is  easily  broken,  especially  in  children,  being  frequently 

the  seat  of  "green-stick"  fracture. 

The  clavicula  and  scapula  together  form  the  shoulder-girdle, 
which  is  open  at  the  back,  but  closed  in  front  by  the 
sternum  placed  between  the  two  claviculas. 


\ 


ii 


Fig.  49. — Left 
Humerus,  An- 
terior Aspect. 

I ,  Shaft  or 
body;  2,  head;  3, 
anatomic  neck;  4, 
greater    tubercle; 

5,  lesser  tubercle; 

6,  7,  8,  9,  mark- 
ings for  muscles; 

10,  orifice  for 
nutrient     artery; 

11,  capitulum; 

12,  trochlea;  13, 
14,  lateral  and 
medial  epicon- 
dyles;  15,  16, 
lateral  and  me- 
dial borders;  17, 
coronoid  fossa. — 
(Gould's  Diet.) 


The  Arm  or  Brachium. 

Humerus. — Long  in  structure  and  shape,  hav- 
ing a  shaft  with  a  medullary  canal  and  two  extremi- 
ties (Fig.  49). 

The  upper  extremity  (proximal  extremity)  in- 
cludes the  head,  neck  and  tubercles. 

The  head  articulates  with  the  glenoid  cavity  of 
the  scapula  to  form  the  shoulder-joint;  the  short, 
thick,  anatomic  neck  joins  the  head  to  the  shaft; 
and  just  below  the  neck  are  the  greater  and  lesser 
tubercles  for  the  attachment  of  muscles  to  rotate 
the  arm.  The  lower  extremity  curves  slightly 
forward  and  presents  two  projections  at  the  sides 
called  the  medial  and  lateral  epicondyles;  the 
medial  is  the  longer  and  consequently  it  is  more 
frequently  broken  off.  Between  the  epicondyles 
are  the  articular  surfaces  for  the  elbow-joint,  the 
trochlea  for  the  ulna  and  the  capitulum  for  the  radius. 

The  shaft  has  three  borders  and  three  surfaces 
(like  all  long  bones). 

The  anterior  and  medial  borders  run  from  the  greater  and 
lesser  tubercles.  In  the  upper  part  they  are  called  the  crests 
of  the  tubercles  and  the  groove  for  the  long  tendon  of  the  biceps 
muscle  is  between  them  (formerly  called  bicipital  groove). 

The  broad,  shallow  groove  containing  the  radial 
nerve  winds  across  the  posterior  surface. 

Note. — The  slender  portion  of  the  shaft  just 
below  the  tubercles  is  called  the  surgical  neck,  be- 
cause it  is  so  often  fractured. 


Forearm,  or  Antebrachium  (Fig,  50). 

Ulna. — A  long  bone  in  structure  and  form,  situated  in  the  medial 
side  of  the  forearm  (the  ulnar  side).     The  upper  extremity  presents 


BONES    OF    THE    UPPER    EXTREMITY. 


53 


two  strongly  marked  processes, — the  olecrancni,  projecting  upward 
from  the  back  and  curving  forward,  and  the  coronoid,  projecting 
forward  from  the  front  and  curving  upward.  Thus  these  processes 
curve  toward  each  other,  and  the  cavity  between 
them  is  the  semilunar  notch.  It  receives  the 
trochlea  of  the  humerus  to  form  the  elbow-joint. 
On  the  lateral  side  of  the  coronoid  process  is  the  „  , 

radial  notch,  where  the  head  of  the  radius  lies.  \\  \ 

The  lower  extremity  is  the  head  of  the 
ulna,  which  lies  in  the  ulnar  notch  of  the  radius. 
There  is  a  well-marked  projection  on  this  head 
called  the  styloid  process. 

The  posterior  border  of  the  shaft  is  subcutaneous  and 
may  be  traced  down  from  the  point  of  the  elbow.  The 
space  between  the  radius  and  the  ulna  is  called  the 
interosseous  space,  and  is  occupied  by  an  interosseous 
membrane. 

Radius. — A  long  bone  in  structure  and  in 
form,  situated  on  the  lateral  side  of  the  forearm 
(the  radial  side). 

The  upper  (or  proximal)  extremity  is  the 
head,  which  is  depressed  at  the  top  to  fit  the 
capitulum  of  the  humerus.  Below  the  head  is 
the  neck,  and  below  that,  in  front,  is  the  tuber- 
osity of  the  radius  for  the  attachment  of  the 
biceps  muscle  of  the  arm.  The  lower  (or  distal) 
extremity  of  the  radius  is  broad  and  t];iick,  and  is 
the  largest  bone  in  the  formation  of  the  wrist-joint. 


On  its  lateral  border  is  the  styloid  process.  Running 
across  the  upper  half  of  its  anterior  surface  is  the  oblique 
line,  which  is  a  part  of  the  anterior  border. 

Special  notes. — The  head  of  the  humerus  is  proximal 
and  articulates  with  the  glenoid  cavity  'of  the  scapula. 
The  head  of  the  radius  is  proximal  and  articulates  with  the 
humerus.     The  head  of  Ike  ulna  is  distal. ' 

The  upper  end  of  the  ulna  is  its  largest  part,  and  an  important  bone  in  the 
elbow-joint.  The  lower  end  of  the  radius  is  the  largest  part,  and  important  in 
the  wrist-joint.  Observe  that  in  the  long  bones  of  the  upper  extremity  the  nutrient 
foramina  are  in  the  shafts  and  are  directed  toward  the  elbow-joint.  They  transmit 
nutrient  arteries  to  nourish  the  bones. 


Fig.  50. — Left 
Ulna  and  Radius, 
Anterior  Surfaces. 
—(Gould.) 

I,  Shaft  or  body 
of  ulna;  2,  semilunar 
notch;  3,  radial  notch 
occupied  by  radial 
head;   4,    olecranon; 

5,  coronoifl  process; 

6,  orifice  for  nutrient 
artery;  7,  interosse- 
ous borders  with  in- 
terosseous space  be- 
tween; 8,  head  of 
ulna;  9,  styloid  proc- 
ess of  ulna;  10,  shaft 
or  body  of  radius;  1 1, 
12,  head  and  neck  of 
radius;  13,  tuberosity 
of  radius;  14,  mark- 
ing for  muscle;  15, 
16,  lower  extremity 
and  styloid  jjrocess. 


54 


anatomy  and  physiology  for  nurses. 
Carpus. 


Fig.  51. — Bones  of  Car- 
pus, Dorsal  Surface. 
• — (Gould's  Dictionary.) 


The  carpal  bones  (ossa  carpi)  are  eight  in  number,  and  are 
typical  short  bones,  They  are  arranged  in  two  slightly  curved 
rows — the  first  and  second — with  the  convexity  of  the  curves  turned 

upward  toward  the  radius,  the  first  row 

articulating  with  it. 

First  Row. 

Navicular  (os  naviculare). — On  the 
radial  side  of  the  wrist,  named  from  its 
shape  which  resembles  a  boat,  and  marked 
by  a  tubercle. 

Semilunar  (os  lunatum). — Well  named 
from  its  half-moon  shape. 

Cuneiform  (os  triquetrum). — Very 
slightly  resembling  a  wedge. 

Pisiform  (os  pisiforme). — Resembling 
the  half  of  a  split  pea,  and  placed  in  front  of  the  cuneiform. 

Second  Row. 

Trapezitmi  (os  multangulum  majus). — On  the  radial  side, 
marked  by  a  ridge. 

Trapezoid  (os  multangulum  minus). — The  smallest  of  the 
carpal  bones. 

Os  magnum  (os  capitatum). — The  largest,  having  head,  neck, 
and  body. 

Unciform  (os  hamatum). — Named  for  its  unciform  or  hook- 
shaped  process. 

When  the  carpus  is  seen  from  the  front,  four  prominent  points 
are  to  be  noted,  namely — the  tubercle  of  the  navicular  and  ridge 
of  the  trapezium,  on  the  radial  side;  the  pisiform  bone  and  hook 
of  the  unciform  on  the  ulnar  side.  These  mark  the  boundaries  of 
a  deep  groove  where  the  long  tendons  of  the  fingers  glide. 

The  Metacarpus  or  Palm  (Fig.  52). 

The  five  metacarpal  bones  (ossa  metacarpalia)  are  lon^  in 
shape  but  have  no  medullary  canal.  Each  has  a  base,  a  shaft,  and 
a  head,  the  head  being  distal.     The  bases  are  articulated  with  the 


BONES    OF    THE    H.A.ND. 


55 


second  row  of  the  carpus,  and  the  heads  with  the  first  row  of  the 
phalanges.  The  first  corresponds  to  the  thumb;  the  second  to  the 
index  finger;  the  third  to  the  middle  finger,  the  fourth  to  the  ring 
finger,  and  \ht  fifth  to  the  little  finger. 

The  spaces  between  them  are  inter- 
osseous spaces  and  are  occupied  by  inter- 
osseous muscles. 

Note. — The  third  metacarpal  bone  (of 
the  middle  finger)  is  the  longest,  and  its 
head  is  the  most  prominent  when  the  hand 
is  clenched,  as  in  making  a  "fist." 

Phalanges. 


These  are  the  bones  of  the  fingers  and 
thumb  (digits).  A  finger  has  three,  first, 
second  and  third;  the  thumb  has  two,  first 
and  second.  They  are  long  in  shape,  but 
without  a  medullary  canal.  Each  has  a 
base,  a  shaft,  and  a  head,  the  head  being 
distal.  The  first  row  of  phalanges  in- 
cludes those  which  are  next  to  the  meta- 
carpal   bones.      The  terminal  phalanges 


Fig.    52. — Right  Hand, 
Palmar  or  Volar  Surface. 

1-9,  Carpus,  and  grooves 
for  tendons;  10-10,  meta 
carpus; 11  11,  phalanges;  12, 
12,  2d  phalanges;  13,  13,  3d 
phalanges;  14,  15,  ist  and 
2d  phalanges  of  thumb. — ■ 
(Gould's  Dictionary.) 


(those  of  the  third  row)  have  each  a  horse- 
shoe-shaped border  on  the  anterior  surface  for  the  support  of  the 
sensitive  finger  tip;  because  these  bones  bear  the  nails,  they  are 
called  the  ungual  phalanges.^ 

Resume. — With  the  limb  in  the  anatomic  position,  observe  the  groove 
for  the  biceps  muscles  on  the  front  of  the  humerus,  beginning  between  the 
greater  and  lesser  tubercles.  In  the  forearm,  note  that  the  ulna  is  the  bone  of 
the  elbow-joint,  while  the  radius  makes  the  wrist-joint;  that  their  shafts  are 
parallel  and  the  palm  is  turned  forward,  and  the  carpus  curved  to  help  in  forming 
the  hollow  of  the  hand  (or  the  "cup  of  Diogenes"),  and  that  the  thumb  is  on 
the  radial  side,  and  free. 

'  This  description  of  the  metacarpal  bones  and  phalanges  follows  that  of  stand- 
ard text-books.  It  would  seem,  however,  more  in  accordance  with  the  facts  to  consider 
the  palm  as  composed  oi  four  metacarpal  bones — one  for  each  finger — and  to  give  to 
the  thumb  three  phalanges,  since  the  bone  commonly  called  the  first  metacarj)al  (or 
the  metacarpal  of  the  thumb)  resembles  those  of  the  first  row  of  the  phalanges  in 
both  form  and  development. 


56 


ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 


ARTICULATIONS  OF  THE  UPPER  EXTREMITY. 

Sterno-clavicular,  a  gliding  joint  {arthrodia). — This  is  the  one 
joint  by  which  the  upper  extremity  articulates  with  the  trunk. 

Articular  surfaces;  on  the  upper  angle  of  the  manubrium  and 
the  sternal  end  of  the  clavicula.  Anterior  and  posterior  ligaments 
connect  the  bones,  forming  a  capsule.  (The  joint  is  divided  by  a 
disc  of  fibro-cartilage  into  two  cavities  and  there  are  two  synovial 
membranes.) 


mm 

-Sterno-clavicular  Joint, — 
The  inter-articular  cartilage  is  shown  in  the  joint  of  the  ri< 

the  left  side. 


(Morris. 

ht  side;  capsules  shown  on 


Motions. — Gliding,  by  which  the  shoulder  moves  upward^ 
downward,  backward  and  forward. 

Ligaments  not  connected  with  the  joint  but  useful  in  preventing  dislocation: — 
The  costo-clavicular,  holding  the  clavicle  to  the  first  rib,  and  the  conoid  and 
trapezoid  connecting  it  with  the  coracoid  process  of  the  scapula. 

Acromio-clavicular. — A  small  gliding  joint  between  the 
acromion  process  of  the  scapula  and  the  acromial  end  of  the  clavicula. 
It  is  enclosed  by  a  capsule. 

Shoulder- joint. — A  ball-and-socket  joint  {enthrosis).  Artic- 
ular surfaces :  the  head  of  the  humerus  and  the  glenoid  fossa  of  the 
scapula.  The  fossa  is  deepened  by  a  rim  of  fibro-cartilage  called 
the  glenoid  margin.  The  capsule  is  attached  to  the  scapula  around 
the  margin  of  the  glenoid  fossa,  and  to  the  humerus  around  the 
anatomic  neck.     It  is  so  loose  that  the  head  of  the  humerus  will 


ARTICULATIONS    OF    THE    UPPER    EXTREMITY. 


57 


fall  an  inch  away  from  the  glenoid  fossa  by  its  own  weight  if  the 
surrounding  muscles  be  removed;  it  contains  a  synovial  membrane 
which  covers  the  glenoid  margin  and  folds  like  a  sheath  around 
the  long  tendon  of  the  biceps  muscle  (Fig.  54). 

Motions. — In  every  possible  direction,  as  flexion,  exiensioUy 
abduction,  adduction,  rotation,  and  circumduction,  with  greater 
freedom  than  any  other  joint  of  the  body, 
because  the  socket  is  so  shallow  and  the 
capsule  is  so  loose. 

Elbow- joint. — A  hinge-joint  {gingly- 
mus)  (Fig.  55). 

Articular  surfaces:  the  trochlea  of  the 
humerus  in  the  semilunar  notch  of  theidna, 
and  the  capitidum  of  the  humerus  in  the 
depressed  head  of  the  radius. 

The  ligaments — anterior,  posterior,  me- 
dial, and  lateral — together  compose  a 
large  capsule.  (They  are  attached  to  the 
humerus  above  the  olecranon  fossa  at  the 
back,  and  above  the  coronoid  and  radial 
fossae  in  front.)  The  synovial  membrane 
is  extensive. 

Motions. — The  elbow-joint  proper  is 
capable  of  flexiofi  and  extension  only,  like 
all  hinge-joints. 


-Left   Acromio 

CLAVICULAR    AND     ShOULDER- 
JOINTS. 

I,  Acromio-clavicular  joint; 
2,3,  conoid  and  trapezoid  liga- 
ments; 4,  transverse  ligament, 
across  suprascapular  notch;  5, 
6,  capsule;  7,  groove  for  biceps 
tendon. — (Potter's  Anatomy.) 


The  radius  and  ulna  are  connected  together  at  their  extremities,  making 
roiling  joints  (see  p.  15);  their  shafts  give  attachment  to  an  interosseous 
membrane  of  white  fibrous  tissue  which  almost  fills  the  space  between  the  bones. 

Wrist-joint. — Between  the  forearm  and  the  carpus,  having  a 
variety  of  gliding  motions,  but  used  principally  as  a  hinge-joint. 
Articular  surfaces :  Above — the  lower  end  of  the  radius  and  the  tri- 
angular cartilage  (or  articular  disc) ;  below — the  first  row  of  carpal 
bones  (not  including  the  pisiform).  The  ligaments — anterior, 
posterior,  medial,  and  lateral — enclose  the  joint  like  a  capsule. 

Motions. — Flexion,  extension,  and  slight  lateral  bending  (or 
from  side  to  side)  making  abduction  and  adduction.  (If  the  hand  is 
bent  far  backward  or  over-extended,  this  is  dorsal  flexion.) 

Surgical   note. — The  anterior  ligament  of   the   wrist-ioint  is 


eg  ANATOMY  AND   PHYSIOLOGY   FOR  NURSES. 

remarkably  strong  and  seldom  torn;  the  lower  end  of  the  radius 
breaks  instead,  under  sudden  great  force,  as  in  Colles'  fracture. 

Carpal. — Eight  bones   arranged   in   two   rows,   bound   firmly 
toc^ether  by  short  ligaments.     Motions — Gliding  only. 

Metacarpal. — ^Five  bones,  articulated  by 
their  bases  to  the  carpios,  and  by  their  heads  to 
the  digits.  Head  of  first,  belonging  to  thumb, 
is  free;  heads  of  others  connected  together  by  a 
transverse  band.  Motions— Slight  gliding,  except 
in  case  of  the  thumb,  which  may  be  flexed  or 
bent  upon  the  palm;  extended  or  straightened; 
abducted  from  hand;  adducted  toward  hand. 


Surgical  note. — In  the  normal  hand,  a  dis- 
location of  the  thumb  is  most  difficult  of  reduc- 
tion, because  the  metacarpal  head  and  the  base 
of  the  first  phalanx  are  interlocked  in  such  a 
manner  as  to  form  what  is  called  a  joint  by 
reciprocal  reception^  or  "saddle  joint." 

Phalangeal. — Three  bones  in  each  finger, 
two  in  the  thumb.  Anterior,  posterior,  and 
lateral  ligaments.  Motions. — Flexion  and  exten- 
sion. 

Note. — In  the  completed  hand,  the  fingers 
and  the  thumb  can  be  moved  from  side  to  side, 
independently;  that  is,  they  can  be  spread  apart 
{abduction)  and  drawn  together  {adduction)  (p.  102). 


Fig.  55. — Left 
Elbow-joint,  Lat- 
eral Aspect. 

I,  Humerus;  2,  3, 
ulna  and  radius;  4, 
lateral  ligament;  5, 
orbicular  or  ring  liga- 
ment; 6,  lateral  por- 
tion of  capsule;  7, 
anterior  portion  of 
capsule;  8,  lateral 
epicondyle.  —  (Pot- 
ter'sAnatomy.) 


Supination  and  Pronation. 

These  are  terms  applied  to  certain  movements  of  the  extremities. 
They  are  best  seen  in  the  forearm  where  they  change  the  position 
of  the  hand. 

The  head  of  the  radius  rests  in  the  radial  notch  of  the  ulna,  held 
there  by  a  circular  band  called  the  ring  ligament  (orbicular) ,  and  it 
can  be  rolled  forward  or  backward,  within  the  ring  (a  form  of  pivot 
joint).  Of  course,  the  shaft  moves  at  the  same  time,  the  lower  end 
turning  forward  or  backward  around  the  head  of  the  ulna,  and  the 


BONES  OF  THE  LOWER  EXTREMITY. 


59 


wrist  and  hand  must  accompany  it.  When  the  radius  and  the  ulna 
are  placed  in  the  anatomic  position,  their  shafts  are  parallel  and  the 
hand  lies  upon  its  back;  this  is  supination.  If  the  radius  rolls 
forward,  the  shafts  become  crossed,  and  the  hand  lies  upon  its 
face;  this  is  pronation. 

Surgical  notes. — Supination  and  pronation  are  very  important 
movements.  If  they  are  prevented  the  hand  loses  much  of  its  useful- 
ness, therefore  fractures  of  the  shafts  would  not  be  set  in  the  position 
of  pronation,  lest  adhesions  should  form  between  the  crossed  shafts, 
preventing  supination. 


BONES  OF  THE  LOWER  EXTREMITY. 
In  the  Thigh . Femur i 


In  the  Leg. 


Tibia 

Fibula 

Talus 

Calcaneus 

Cuboid. 

In  the  Tarsus^ .    |   Navicular  bone. 

ist  cuneiform.  . 

2d  cuneiform. ...    I 

3d  cuneiform. ...    J 

Metatarsus — 5  metatarsal  bones 5 

Toes  and  Digits — 14  phalanges 14 

Patella — i  sensamoid  bone i 


ist  row. 


2d  row. 


^As  given  by  Spalteholtz — 
Talus  \ 


Calcaneus 
(os  calcis) 


J 


ist  row 


Os  cuboideum 
Os  naviculare  pedis 
Os  cuneiforme      I 
Os  cuneiforme    II 
Os  cuneiforme  III 


30 


2d  row. 


The  Thigh. 

Femur. — The  largest  bone  in  the  body. 

Its  upper  extremity  presents  a  nearly  spherical  head  joined 
by  a  neck  to  the  shaft,  and  resting  in  the  acetabulum.  At  the 
junction  of  the  neck  and  shaft  are  the  two  trochanters, — the  tro- 
chanter major  on  the  lateral  side,  and  the  trochanter  minor  on  the 
medial  and  posterior  side.     The  lower  extremity  presents  two 


6o 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


condyles  projecting  downward,  the  medial  and  the  lateral.  The 
medial  is  slightly  longer  and  the  lateral  slightly  broader  of  the  two; 
and  the  deep  notch  between  them  is  called  the  intercondyloid  notch 
or  fossa.  There  is  a  projection  from  the  side  of  each  condyle 
called  the  medial  and  the  lateral  epicondyle. 


Fig.  56. 


-The  Femur,  Left  Poste- 
rior Aspect. 


I,  I,  Linea  aspera;  2,  2,  3,  divisions 
of  linea' aspera;  4,  4,  divisions  of  linea 
aspera;  5,  6,  head,  and  mark  for  liga- 
mentum  teres;  7,  neck;  8,  9,  trochanter 
major;  10,  trochanter  minor;  11,  12,  lat- 
eral and  medial  condyles;  13,  intercon- 
dyloid notch;  14,  15,  lateral  and  medial 
epicondyles, — (Gould's  Dictionary.) 


Fig.  57. — Left  Tibia  and  Fibula, 
Anterior  Aspect. 

I,  Shaft  or  body  of  tibia;  2,  3,  me- 
dial and  lateral  condyles;  4,  spine  or 
intercondyloid  eminence;  5,  tubercle  of 
tibia;  6,  crest  or  shin;  7,  8,  lower  ex- 
tremity, and  medial  malleolus;  9,  shaft 
or  body  of  fibula;  10,  upper  extremity  or 
head  of  fibula;  11,  lower  extremity  and 
lateral  malleolus. — (Gould'sDictionary.) 


The  shaft  has  a  prominent  posterior  border  called  the  linear 
aspera.  This  divides  lower  down  into  two  lines  running  to  the  con- 
dyles and  enclosing  a  smooth  triangular  space  called  the  popliteal 
space,  or  plane  of  the  femur.     The  other  borders  are  not  plainly  seen. 


boxes  of  the  lower  extremity,  6l 

The  Leg  (Fig.  57). 

Tibia. — A  long  bone  in  the  medial  side  of  the  leg.  Its  upper 
extremity  is  the  head,  which  is  composed  of  two  cmidyles,  medial 
and  lateral,  having  shallow  depressions  on  the  top  to  bear  the 
condyles  of  the  femur.  Between  these  depressions  is  the  inter- 
condyloid  eminence,  or  spine  of  the  tibia.  The  tuberosity  of  the 
tibia  is  a  large  elevation  in  front,  just  below  the  head.  The  lower 
extremity  has  a  projection  downward  from  its  medial  surface 
called  the  medial  malleolus,  which  helps  to  form  the  ankle-joint. 

The  shaft  has  a  prominent  anterior  border  called  the  cresi 
or  shin,  which  is  plainly  felt  under  the  skin.  This  border  and  the 
medial  surface  are  both  called  subcutaneous  because  no  muscles 
cover  them. 

Fibula. — A  long  bone,  in  the  lateral  side  of  the  leg,  slender  and 
easily  broken.  Its  upper  extremity  is  the  head,  which  has  a 
short  styloid  process  pointing  upward.  The  lower  extremity  is 
the  lateral  malleolus,  which  helps  to  form  the  ankle-joint. 

Note. — The  space  between  the  tibia  and  fibula  is  called  the  interosseous 
space,  and  is  occupied  by  interosseous  membrane. 

The  lower  extremities  of  these  two  bones  form  the  prominences 
at  the  side  of  the  ankle  known  as  the  ankle-bones;  they  are  the 
medial  and  the  lateral  melleoli,  which,  being  subcutaneous,  are 
especially  exposed  to  blows. 

Special  notes. — Observe  that  the  heads  of  all  three  bones  are  proximal; 
that  (he  fibula  does  not  form  any  part  of  the  knee-joint;  that  ih.&  nutrient  foramina 
all  run  from  the  knee. 

The  Tarsus  (Fig.  58). 

There  are  seven  tarsal  bones  arranged  in  two  irregular  rows  to 
form  the  arches  of  the  foot,  or  instep. 

First  Row. 

Talus  (astragalus). — On  the  tibial  side.  Has  a  head,  a  neck, 
and  a  body;  the  body  is  received  between  the  two  malleoli  to  form 
the  afikle-joint,  and  the  head  is  turned  forward  toward  the  toes. 
It  rests  upon  the  calcaneus. 


62 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


Calcaneus  (os  calcis)  or  bone  of  the  heel. — The  largest  tarsal 
bone.  It  is  under  the  talus  (astragalus),  and  bears  the  weight  of 
the  entire  body  in  the  erect  position.  The  tuberosity  of  the  cal- 
caneus projects  backward  beyond  the  ankle,  and  gives  attachment 
to  the  largest  tendon  in  the  body,  the  tendon  of  Achilles  (tendo 
A  chillis). 


Calcaneus 


Talus 


Scaphoid,  or  navicular 


First  cuneiform 


Tarsus 


Metatarsus 


Phalanges 


Fig.  58. — Bones  of  Left  Foot. — (Morris.) 

Second  Row. 

Navicular  (os  naviculare). — On  the  tibial  side,  in  front  of  the 
talus,  articulating  with  its  head. 

Cuneiform  bones  (or  wedge-shaped  bones). — In  front  of  the 
navicular.     They  are  three  in  number,  first,  second,  and  tliird. 

Cuboid  (os  cuboideum). — It  lies  in  front  of  the  calcaneus. 


articulations  of  the  lower  extremity. 
The  Metatarsus. 


63 


The  five  metatarsal  bones  in  the  foot  resemble  the  metacarpal 
bones  of  the  hand  in  their  general  characteristics,  with  some  special 
developments;  the  interosseous  spaces  between  them  are  occupied 
by  interosseous  muscles. 

Phalanges. 

Fourteen  in  number,  as  in  the  hand,  and  arranged  in  a  similar 
manner — two  for  the  great  toe,  and  three  for  each  of  the  other  toes. 
Note. — The  great  toe  is  in  the  medial  border  of  the  foot. 


A.  B. 

Fig.  59. — Left  Patella.  A  ,  Anterior  Surface,  B,  Posterior  Surface.— (Morris.) 

Patella. 

The  patella  is  the  largest  sesamoid  bone.  It  is  triangular  in 
shape,  placed  in  front  of  the  "knee-joint,  and  held  to  the  tuber- 
osity of  the  tibia  by  a  strong  band  about  three  inches  long — the 
so-called  ligament  of  the  patella.  Its  location  while  the  body  is 
erect  is  in  front  of  the  condyles  of  the  femur,  but  in  the  sitting 
position  it  is  in  front  of  the  lower  ends  of  the  condyles,  and  in  kneeling 
it  is  beneath  them, 

ARTICULATIONS   OF  THE  LOWER  EXTREMITY. 

Hip-joint  (ball-and-socket  joint  {Enar  thro  sis),  Fig.  60).^ 
Articular  surfaces:  head  of  the  femur,  and  the  acetahdum  deepened 
by  the  glenoid  rim  of  the  acetabulum  (a  rim  of  fibro-cartilage). 
The  bones  are  directly  connected  by  the  ligamentum  teres  (or  round 
ligament)  within  the  joint,  which  is  attached  by  one  extremity  near 


64 


ANATOMY  AND   PHYSIOLOGY    FOR   NURSES. 


Tendon  of  biceps 
musde 


Capsule 


Fig.  6o. — Hip-joint. — (Morris.) 


■■Capsule 
Glenoid  run 


Fig.  6i. — Ligamentum  Teres. — (Morris.) 


ARTICULATIONS    OF    THE    LOWER    EXTREMITY. 


65 


the  middle  of  the  head,  and  by  the  other  to  the  bottom  of  the 
acetabulum  (Fig.  61). 

A  capsule  encloses  the  joint  (Fig.  60).  It  is  strengthened  by 
special  bands  of  fibers  extending  to  surrounding  bones, — one,  the 
ilio-femoral  from  the  ilium  to  the  great  trochanter,  resembles  an 
inverted  letter  Y,  and  was  formerly  called  the  Y-ligament;  also  the 
ligament  of  Bigelow.  The  synovial  membrane  not  only  lines  the 
capsule  but  invests  the  ligamentum  teres. 


ratty  tissue 


Synovial  membrane  re- 
flected off  crucial  liga- 
ments 
Cut  end  of  anterior  cru- 
cial ligament 
Posterior  crucial  liga- 
ment 


Extension  of  synovial  sac  of  knae 
upon  femur 


Tendon    of    quadriceps    extensor, 
forming  flbrous  capstile  of  Joint 


PATELU 
Pre-patellar  bursa 

CONDYLE  OF  FEMUR  (INNER) 
Ligamentum  mucosum 


Patty  tissue  between 
ligamentum  patellae 
and  synovial  aac 


Bursa  beneath  ligamentum 
patellae 


Fig.  62. — Lnterior  of  Knee-joint. — (Morris.) 


Motions. — Free   motion   in    every   direction,   like   that  of  the 
shoulder. 

Knee-joint  (hinge  or  ginglymus  joint)  (Fig.  62). — Articular 
surfaces:  the  condyles  of  the  femur,  the  head  of  the  tibia,  and  the 
posterior  surface  of  the  patella.  The  two  surfaces  on  the  top  of 
the  tibia  are  shallow,  but  their  depth  is  increased  by  semilunar 
fibro-cartilages  attached  around  the  borders,  thus  forming  shallow 
cups  for  the  condyles. 
5 


66 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


The  femur  and  tibia  are  directly  connected  by  two  ligaments 
within  the  joint,  which  cross  each  other  and  are  therefore  called  the 
crucial  ligaments.  (One  passes  from  the  front  of  the  spine  to  the 
lateral  condyle,  the  other  passes  from  behind  the  spine  to  the 
medial  condyle.)  The  patella  lies  in  front  of  the  condyles,  being 
imbedded  in  a  thick  tendinous  band  about  three  inches  long  which 
continues  to  the  tuberosity  of  the  tibia.  This  band  is  really  the 
tendon  of  insertion  for  some  thigh  muscles,  and  is  improperly 
called  the  ligament  of  the  patella.     It  serves  as  the  anterior  liga- 


Plantar  ligaments 

Fig.  63. — Ligaments  of  the  Ankle-joint  and  Plantar  Region. — (Morris.) 

ment  of  the  joint  but  is  at  the  same  time  the  quadriceps  extensor 
tendon,  sometimes  called  the  patellar  tendon.  There  are  distinct 
medial  and  lateral  ligaments,  and  some  strong  oblique  bands  at  the 
back;  and  all  are  connected  by  a  capsule  which  encloses  the  joint 
cavity. 

The  synovial  membrane  is  very  extensive  (Fig.  62);  it  covers  the 
crucial  ligaments  and  semilunar  cartilages. 

Motions. — Flexion,  extension,  and  very  limited  rotation  of  the  leg. 


Note. — The  patella  cannot  be  drawn  upward  under  any  circumstances. 
When  the  knee  is  flexed,  it  lies  against  the  lower  ends  of  the  condyles,  and  in 


ARTICULATIONS    OF    THE    LOWER    EXTREMITY. 


67 


kneeling  the  condyles  rest  upon  it.  The  elasticity  of  the  great  muscles  to  which 
the  patellar  tendon  belongs,  allows  very  free  motion  and  at  the  same  time  keeps 
the  patella  always  in  place  close  to  the  condyles. 

Bursae. — There  are  several  small  cavities  called  bursae,  the  use  of  which 
is  to  prevent  friction  in  the  tissue  outside  the  knee-joint.  They  usually  com- 
municate with  the  joint.  The  largest  one  is,  however,  subcutaneous,  being 
in  front  of  the  patella  between  it  and  the  skin.     (Fig.  62  and  page  77.) 

Surgical  note. — This  prepatellar  bursa  is  subject  to  frequent 
pressure  and  easily  becomes  inflamed  and  enlarged,  making  the 
so-called  "housemaid's  knee." 

Ankle-joint,  (hinge-joint). — Articular  surfaces  on  the  medial 
and  lateral  malleoli  and  the  body  of  the  talus.  They  are  connected 
by  anterior,  posterior,  medial,  and  lateral  ligaments. 


Tendo  Achillis 
Talus  Vessels  and  nerve 


Scaphoid 


First  cuneiform 
First  metatarial 


Calcaneus 
Muscles  of  plantar  region 

Fig.  64. — Medial  Border  of  Right  Foot,  Showing  Bones  in  Position. — (Morris.) 


The  medial  is  often  called  the  deltoid  ligament,  from  its  shape  i  like  the 
Greek  letter  delta,  and  the  lateral  ligament  is  in  three  distinct  bands,  the  anterior, 
middle,  and  posterior. 

Motions. — Flexion,  extension,  and  slight  abduction  and  adduction; 
also  lifting  the  medial  border,  or  eversion,  and  lifting  the  lateral 
border,  or  inversion. 

Notes. — The  transverse  ligament  is  a  special  band  behind  the  talus,  connecting 

the  two  malleoli,  to  prevent  backward  dislocation  of  foot  in  jumping,  running,  etc. 

There  is  no  motion  of  the  lower  extremity  which  corresponds  to  supination 


68  ANATOMY  AND   PHYSIOLOGY    FOR   NURSES. 

in  the  upper,  the  whole  extremity  being  in  the  permanently  pronated  position, 
which  brings  the  great  toe  toward  the  median  line  of  the  body,  or  on  the  medial 
border  of  the  foot.     (The  thumb  is  on  the  lateral  border  of  the  hand.) 

Tarsal. — An  interosseous  ligament  connects  the  talus  to  the 
calcaneus;  it  is  the  strongest  one  in  the  body.  Short  fibrous  bands 
connect  the  various  tarsal  bones  to  each  other  to  complete  the 
instep,  and  there  is  one  elastic  ligament  upon  which  the  head  of  the 
talus  rests.  It  assists  to  prevent  excessive  jarring  as  the  foot  strikes 
the  ground.  (This  is  the  only  ligament  containing  elastic  tissue  in 
the  extremities.) 

Metatarsal. — Like  the  metacarpal,  except  that  the  heads  are  all 
joined  together  by  a  transverse  band;  the  great  toe  is  not  free. 

Phalangeal. — Like  those  of  the  hand. 

Arches  of  the  foot. — The  principal  arch  is  from  the  heel  to 
the  ball  of  the  foot;  a  second  one,  the  transverse,  is  equally  impor- 
tant. The  arteries  and  nerves  in  the  sole  of  the  foot  are  protected 
from  pressure  by  these  arches,  which  are  preserved  not  only  by 
the  ligaments  and  the  shape  of  the  bones,  but  by  the  tendons  of 
certain  muscles. 

Practical  points. — In  walking  the  weight  is  transmitted  principally  through 
the  talus,  the  navicular,  and  three  cuneiform  bones  to  the  three  medial  toes, 
giving  the  "springy"  step  to  the  well-arched  foot.  In  standing,  it  falls  more  upon 
the  calcaneus,  and  is  distributed  through  the  cuboid  to  the  two  lateral  toes  as 
well. 

Resume. 

Comparing  the  joints  in  the  upper  and  lower  extremities,  note 
that  both  the  shoulder  and  hip  are  ball-and-socket  joints;  that  the 
elbow  and  knee  are  hinge-joints,  as  are  also  the  wrist  and  ankle; 
but  whereas  in  the  wrist  extension  is  limited,  in  the  ankle  it  is  so 
free  as  to  bend  the  top  of  the  foot  almost  against  the  leg,  becoming 
dorsal  Jlexion,  and  is  actually  csdltd  Jlexion  of  the  ankle-joint,  the 
term  extension  being  used  to  signify  the  act  of  straightening  the 
foot  in  a  line  with  the  leg. 

The  back  of  the  hand  and  the  top  of  the  foot  are  both  called 
the  dorsum;  the  face  of  the  hand  is  the  palm  or  volar  surface,  and 
the  sole  of  the  foot  is  the  plantar  surface.  The  thumb  is  free;  the 
great  toe  is  bound  with  the  others. 


ARTICULAR    NERVES.  69 

The  following  table  of  articular  nerves  is  inserted  in  this  place 
for  convenient  reference,  when,  in  the  care  of  painful  joint  affec- 
tions, the  nurse  may  be  interested  to  know  the  names  of  the  par- 
ticular nerves  involved. 

NERVE  SUPPLY  TO  THE  PRINCIPAL  JOINTS. 

Temporo-mandibular.  .  Fifth  cranial  or  trifacial. 

Shoulder Suprascapular,  subscapular,  axillary. 

Elbow. Musclo-cutaneous  (principally). 

Wrist  and  hand. Ulnar,  median,  deep  branch  of  radial. 

Joints  of  spinal  column.  Spinal  nerves. 

Hip Femoral,  obturators,  sciatic. 

Knee Femoral,  obturator,  tibial,  peroneal. 

Ankle  and  foot Deep  branch  of  peroneal,  two  plantar  nerves. 


CHAPTER  V. 
COMPLETION,  REPAIR  AND  FUNCTIONS  OF  BONES. 

Notes  Concerning  the  Completion  of  Long  Bones. 

In  the  humerus,  radius,  and  ulna,  the  nutrient  canals  lead  toward  the  elbow 
and  the  bones  are  completed  here  at  an  earlier  date  than  at  the  wrist  or  shoulder. 
In  the  femur,  tibia,  and  fibula,  the  nutrient  canals  lead  away  from  the  knee;  and 
the  bones  are  completed  first  at  the  hip  and  the  ankle. 

Surgical  notes. — The  time  of  union  of  the  extremities  and  shafts  of  long  bones 
is  important  from  a  surgical  viewpoint.  Thus,  in  the  ends  of  bones  at  the 
elbow-joint  the  extremities  join  the  shafts  at  about  the  seventeenth  or  eighteenth 
year;  therefore,  injuries  near  the  elbow-joint  before  this  age  may  cause  a  separa- 
tion of  the  parts,  called  an  epiphyseal  fracture.  The  upper  end  of  the  humerus 
and  lower  ends  of  the  radius  Sindulna  unite  with  their  shafts  at  about  the  twentieth 
year;  therefore,  in  the  case  of  an  injury  of  the  shoulder  or  wrist  before  this  age 
the  same  possibility  is  borne  in  mind. 

In  the  lower  extremity  certain  differences  are  noted,  since  the  nutrient  arteries 
run  differently.  The  bones  are  completed  first  at  the  upper  end  of  the  thigh,  at 
about  nineteen,  and  at  the  lower  end  of  the  leg  at  about  eighteen  or  twenty  years^ 
while  the  knee  is  completed  last,  at  between  twenty  and  twenty-five. 

It  is  important  for  the  nurse  to  understand  something  of  the 
nature  of  the  baby's  skeleton.     The  general  condition  at  certain 
^       periods  of  life  is  also  of  interest. 
» 

Brief  Survey  of  the  Skeleton  at  Different  Ages. 

At  birth : 

Head .' . .  .Skull-hone?,  have  unossified  borders  and  angles,  therefore, 

the  membrane  is  soft  at  the  fontanelles;  the  base  of  the 
skull  is  largely  in  cartilage,  and  the  bones  are  slightly 
movable. 
Face-hone?,  small  and  very  incomplete. 

Spinal  column Bodies  of  vertebrae  partially  ossified,  with  much  cartilage 

between  them. 
Arches,  each  in  two  separate  pieces  or  halves. 

Pelvic-girdle Hip-bones  (ossa  coxae)  in  two  pieces,  well  separated  by 

cartilage. 
Sacrum  partially  ossified. 
Coccyx  not  at  all  ossified. 

Ribs Shafts  only  are  bony. 

70 


DEVELOPMENT    OF    BONES.  7I 

Sternum Presents  a  number  of  small  centers,  imbedded  in  carti- 
lage. 

Upper  extremity Shmdder-girdle  ossified  at  acromial  end  of  clavicula  and 

in  body  of  scapula;  other  parts  are  cartilage. 
Long  bones — Shafts  partially  ossified. 
Carpus — all  bones  entirely  cartilaginous. 

Lower  extremity Long  bones — Shafts  partially  ossified;  at  the  knee  the 

ends  of  the  femur  and  the  tibia  have  begun  to  ossify. 
Tarsus — three  bones  (talus,  calcaneus,  and  cuboideum) 

have  begun  to  ossify. 
The  metacarpal,  metatarsal  and  phalangeal  bones  have 
thin  lines  of  osseous  tissue  before  birth. 
At  age  of  20  years  : 
Head     1 

Hands   [    All  completed. 

Feet       J 

Long  bones All  completed  except  tibia  and  fibula  whose  upper  ends 

are  not  yet  united  with  the  shafts. 

Ribs  1  A      •     .         •  u 

}    Are  m  two  pieces  each. 

Sternum     J 

Shoulder-girdle Clavicula,  sternal  end  still  separate.     Scapula  soft  at 

borders  and  processes. 
Pelvic-girdle Hip-bones  (ossa  coxae)  completed.     Sacrum  and  coccyx 

still  in  two  or  more  pieces. 

Spinal  column All  parts  ossified. 

At  age  of  25  years :. .  .The  skeleton  is  practically  completed.     The  bones  are 

strong,  and  the  proper  proportions  of  animal  and 

mineral  matter  are  preserved  during  adult  life. 
The  coccyx  may  unite  with  the  sacrum  in  middle  life, 

thus  modifying  one  of  the  diameters  of  the  pelvic 

outlet. 
In  old  age : There  is  no  more  growth.     The    supply    of    animal 

matter  decreases,  and  the  bones  become  brittle  so 

that  they  may  be  easily  broken. 

P01NT.S    OF   Practical    Interest    Concerning    the    Bones    in 

Infancy. 

First,  the  baby's  bones  are  soft,  and  are  still  largely  composed 
of  cartilage.  Second,  since  the  process  of  ossification  is  going  on 
continually,  the  proper  shape  of  the  cartilage  should  be  preserved 
in  order  that  the  shape  of  the  future  bone  may  be  normal.  In 
infancy  the  skull  bones  are  movable  as  well  as  soft,  and  the  shape 
of  the  baby's  head  may  be  altered  by  pressure.  Witness  the  Flat- 
head Indians,  who  bind  a  board  across  the  top  of  the  infant's  skull. 


72,,  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

The  spine  and  the  vertebral  extremities  of  the  ribs  are  com- 
posed largely  of  cartilage;  it  is  therefore  evident  that  not  only  should 
a  baby's  back  be  supported,  but  the  child  should  rest  in  a  horizontal 
position,  the  spine  being  so  soft  that  it  cannot  easily  be  held  upright, 
even  if  the  little  muscles  were  strong  enough  to  do  this  without 
fatigue. 

The  pelvis  and  hip. — During  the  first  year  or  two  both  the 
sacrum  and  the  coccyx  are  still  in  separate  pieces,  while  the  centers 
in  the  three  portions  of  the  hip-hones  are  well  separated  by  carti- 
lage, leaving  the  acetabulum  unossified;  the  head  of  the  femur  is 
also  soft.  Consequently,  a  thought  only  is  needed  to  explain  why  the 
clothing  about  a  baby's  hips  should  leave  them  free  from  pressure. 

Note. — An  advantage  is  derived  from  the  softness  of  the  skeleton 
during  childhood,  as  the  many  jarrings  and  tumbles  incident  to 
the  child's  experience  are  far  less  injurious  to  the  jelly-like  frame 
than  they  would  be  to  a  harder  one. 

Green-stick  fracture. — Up  to  the  age  of  four  years  the  bones 
are  sufficiently  soft  to  hend  rather  than  break,  as  an  older  bone 
would  do  under  similar  circumstances.  Usually  some  of  the 
fibers  do  break,  but  not  the  whole  bone;  this  is  called  a  green- 
stick  fracture,  because  the  bone  behaves  like  a  bough  of  green 
wood  when  forcibly  bent. 

Rachitis  or  rickets. — In  this  disease  ossification  is  delayed, 
and  the  bones  are  more  soft  and  yielding  than  usual  until  completely 
ossified.  The  extremities  grow  larger  and  the  shafts  are  often  bent. 
When  the  mineral  salts  are  finally  deposited  the  bone  is  permanently 
misshapen. 

Spina  bifida. — In  the  formation  of  the  vertebrae,  the  com- 
pletion of  the  arches  and  spinous  processes  occurs  latest  in  the  lower 
lumbar  and  upper  sacral  region.  Sometimes  it  is  not  perfect, 
and  the  spinal  canal  is  then  left  open.  This  condition  is  known 
as  spina  bifida  and  the  membranes  and  fluid  of  the  spinal  cord 
protrude,  forming  a  tumor  upon  the  child's  back.  Spina  bifida 
occurs  rarely  in  other  regions. 

Repair  of  Bone. 

When  a  bone  is  broken  nature  repairs  it  in  her  own  way. 
First,  more  blood  flows  to  the  part;  then  a  certain  amount  of 
animal  matter  like  cartilage,  appears  about  the  fracture,  forming 


REPAIR   AND    PHYSIOLOGY    OF    BONES.  73 

a  callus.  This  is  soon  hardened  by  deposit  of  mineral  matter  and 
the  callus  becomes  bone,  but  the  mark  of  fracture  and  repair  will 
always  remain.  The  callus  will  form  and  unite  the  ends  of  bone 
even  if  they  are  not  well  matched,  but  in  this  case  deformity  will 
result. 

Surgical  note. — "Setting"  a  fractured  bone  consists  in  placing 
the  ends  in  proper  position,  or  "apposition."  This,  nature  cannot 
do,  because  the  muscles  above  and  below  are  pulling  them  out  of 
place,  therefore  the  skill  of  the  surgeon  is  required  for  its 
accomplishment. 

Practical  point. — The  nursing  care  of  a  fracture  is  directed  to 
the  end  of  keeping  the  bone  supported  in  position,  and  as  far  as  may 
be,  perfectly  quiet  until  the  callus  is  hardened,  so  that  the  least 
possible  deformity  will  remain.  To  accomplish  this  the  nurse  must 
not  only  have  a  knowledge  of  anatomy,  but  must  exercise  skill  and 
judgment  to  an  unusual  degree. 

PHYSIOLOGY  OF  BONE  AND  THE  SKELETON. 

At  first  thought  it  would  appear  that  not  much  could  be  said 
concerning  the  physiology  of  bone  tissue,  which  is  a  finished  product, 
the  changes  which  it  undergoes  being  directed  solely  to  its  own  pres- 
ervation. The  ability  of  bone  to  repair  injuries  by  utilizing  ma- 
terial from  the  blood  is,  however,  a  physiological  process;  and  the 
membranes  which  cover  bony  surfaces  (periosteum  outside,  endos- 
teum  within  medullary  canals)  have  a  well-defined  function  in  the 
formation  of  bone  tissues,  already  referred  to.  One  of  the  most 
important  functions  of  the  body,  namely: — providing  an  origin  for 
cells  (or  corpuscles)  of  the  blood,  belongs  to  the  marrow  of  bones. 
Cancellous  bone  contains  in  its  spaces  thin  red  marrow  (the  "red 
bone  marrow"  of  clinic  use)  in  which  red  cells  have  their  origin, 
while  the  medullary  canals  of  long  bones  contain  a  firmer  fatty 
maiTow  where  many  of  the  white  cells  of  the  blood  have  their 
beginning. 

Taking  a  broad  view,  we  find  many  points  of  interest  in  the  bones 
and  the  skeleton  which  they  comprise,  some  of  which  have  already 
been  touched  upon.  It  is  their  mechanical  physiology  which  is  con- 
spicuous and  of  great  importance — they  afford  attachment  to  mus- 
cles; they  enclose  cavities;  they  sustain  pressure. 


74  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

Their  usefulness  is  due  to  their  physical  characteristics — for 
instance,  the  hardness  of  bones  enables  the  framework  which  they 
compose  to  support  the  soft  parts  of  the  body,  and  in  certain  localities 
enables  them  to  protect  internal  organs.  An  important  example  is 
the  neural  canal  with  its  contents — the  brain  and  spinal  cord. 

Again,  it  is  this  same  quality  of  hardness  which  enables  the  skel- 
eton to  bear  direct  pressure  and  the  body  weight.  Osseous  tissue 
in  certain  bones — notably  the  femur  and  the  os  coxae — is  especially 
arranged  in  lines  of  pressure  for  this  purpose;  namely,  that  super- 
imposed weight  may  be  borne  with  the  least  strain  upon  the  bone. 

The  relation  between  the  shapes  of  bones  and  the  arrangement 
of  their  two  tissues  has  a  direct  bearing  upon  their  usefulness  and 
the  convenience  with  which  it  is  exercised. 

Examples  are  seen  in  the  long  bones — their  (comparatively) 
large  extremities  enter  into  the  formation  of  joints;  they  also  give 
attachment  to  many  muscles  which  move  the  joints.  Here,  extent 
of  surface  is  needed  and  cancellous  bone  is  used  with  but  a  thin 
covering  of .  compact,  thus  securing  the  necessary  surface  without 
undue  weight.  Their  shafts  give  attachment  to  fewer  muscles,  but 
their  position  in  the  extremity  exposes  them  to  violence  (applied 
transversely)  and  calls  for  endurance  of  strain.  Hence,  for  these 
two  reasons — first,  that  extent  of  surface  is  unnecessary;  and  second, 
that  strength  and  endurance  are  demanded — the  compact  tissue 
is  appropriate.  It  also  secures  a  convenient  slenderness  of  bone 
where  the  bulk  of  muscle  tissue  is  greatest. 

By  far  the  greatest  variety  of  functions  is  seen  in  the  articulated 
skeleton,  whereby  the  movements  necessary  to  the  well-being  of  the 
individual  are  made  possible  by  the  character  of  the  joints. 

The  movements  of  the  trunk  are  limited,  but  sufficient  for  the 
needs  of  the  organs  which  it  contains;  while  those  of  the  extremities 
are  many  and  free.  They  may  resist  external  force;  they  may 
themselves  overcome  opposing  forces.  They  may  be  used  as 
weapons  of  offense  or  defense.  Facilities  for  tansporting  the  body 
from  place  to  place,  or  locomotion,  are  provided  by  the  articulated 
bones  of  the  lower  extremities;  and  the  power  of  the  upper  ex- 
tremities to  perform  a  thousand  necessary  acts  would  not  exist 
without  a  similar  framework.  These  points  have  been  mentioned 
already,  and  will  be  dwelt  upon  later  in  connection  with  the  study 
of  the  muscular  system. 


CHAPTER  VI. 

THE    CONNECTIVE    TISSUE    FRAMEWORK    AND     THE 
SKELETAL  MUSCLE  SYSTEM. 

THE  FASCI.E  OF  THE  BODY  AND  MUSCLES  OF   THE 
HEAD  AND  TRUNK. 

Although  present  In  every  part  of  the  body,  the  connective  tissue 
is  so  conspicuously  associated  with  the  muscle  system  that  a  few 
facts  of  interest  concerning  this  universal  tissue  are  here  reviewed, 
before  commencing  the  study  of  the  muscles. 

For  muscles  it  is  a  veritable  framework,  as  will  be  seen.  In 
fibrmis  form  it  is  conspicuous  on  their  surfaces  as  sheaths,  or  as 
separating  one  from  another;  and  in  tendons.  As  delicate  areolar 
tissue  it  invades  them,  bearing  tiny  vessels  and  nerves  and  forming 
tissue-spaces. 

This  it  does  in  all  organs — wrapping  them,  supporting  their 
cells,  and  invading  them  to  convey  vessels  and  nerves.  It  fills  in 
spaces  between  organs,  and  accompanies  large  vessels  to  and  from 
them.  It  connects  organs  to  each  other;  and  everywhere  it  forms  a 
network  of  tissue-spaces  containing  nutritive  fluid  obtained  from 
the  blood-vessels  for  the  cells  of  the  body. 

If  one  could  imagine  that  everything  in  the  human  body  except 
connective  tissue  could  be  destroyed,  the  remaining  portion  would 
bear  the  same  relation  to  the  body  that  had  been,  as  a  skeleton  leaf 
bears  to  a  fresh  green  one. 

THE  FASCLE  OF  THE  BODY. 

The  word  fascia  is  applied  to  the  connective  tissue  which  sur- 
rounds various  organs  or  lines  cavities.  Fascia  is  found  in  every 
part  of  the  body,  and  we  shall  study  here  two  varieties,  which  are 
associated  with  the  muscles  and  skin.  They  are  called  the  deep 
and  the  superficial  fascia. 

The  deep  fascia. — This  is  a  firm  layer  of  connective  tissue 
with  but  small  spaces  between  its  fibers,  therefore  it  is  dense  and 

75 


76 


ANATOMY  AND   PHYSIOLOGY    FOR   NURSES. 


tough.  It  is  white  and  smooth,  and 
seldom  contains  any  fat.  The  deep 
fascia  covers  the  muscles  and  binds 
them  down,  and  also  separates  them 
into  groups,  thus  forming  intermus- 
cular septa.  (Many  muscle  fibers 
arise  from  intermuscular  septa.) 
(Fig.  65.) 

Special  points. — The  inguinal  liga- 
ment (Fig.  74)  is  a  band  of  the  deep 
fascia  between  the  spine  of  the  ilium  and 
the  tubercle  of  the  pubes.  It  feels  like  a 
cord  from  one  bone  to  the  other.  The 
fascia   lata   {broad  fascia)   is   the  deep 


Fig.  65. — Deep  Fascia  of  Thigh 
(Partial).  6,  7,  8,  10,  14,  indicate 
portions  of  fascia  lata. — (Gould's 
Dictionary.) 


Fig.  66. — Showing  Oval  Fossa. 
The  superficial  fascia  has  been  dis- 
sected away,  leaving  cutaneous  veins 
lying  upon  deep  fascia. 


fascia  of  the  thigh;  it  is  thicker  and  stronger  than  any  other  fascia  of  the 
body.  It  is  attached  to  the  hip-bones  above  and  the  leg-bones  below.  A 
■portion  which  is  especially  tense  and  strong  may  be  felt  on  the  lateral  side  of 


FASCIA    OF    THE    BODY.  77 

the  thigh,  above  the  tuberosity  of  the  femur,  like  a  tight  band  attached  to  the 
tibia;  it  is  called  the  ilio-tibial  band.     See  page  105,  tensor  fascia  lata. 

The  oval  fossa  or  saphenous  opening  in  the  fascia  lata  is  an 
inch  and  a  half  below  the  medial  portion  of  the  inguinal  ligament. 
It  allows  the  long  saphena  vein  to  pass  through  to  the  femoral  vein 
(Fig.  66  ). 

The  lumbar  fascia  is  not  a  part  of  the  general  deep  fascia 
of  the  body,  but  belongs  to  the  transversus  muscle  described  on 
p.  90.  It  is  attached  behind  to  the  lumbar  vertebrce,  above  to  the 
last  tivo  ribs,  and  below  to  the  crest  of  the  ilium. 

The  superficial  fascia  covers  the  deep  fascia.  It  lies  immedi- 
ately beneath  the  skin  in  its  whole  extent  and  consists  of  loose- 
meshed  connective  tissue,  arranged  somewhat  in  layers,  and  con- 
taining the  subcutaneous  fat.  It  also  imbeds  the  superficial  or 
cutaneous  arteries,  veins,  and  nerves  between  its  layers.  In  places 
where  the  fascia  is  thin,  as  on  the  back  of  the  hand,  the  veins  are 
easily  seen.  This  fascia  is  closely  connected  with  the  skin,  and 
they  glide  together  over  the  deeper  structures. 

A  bursa  is  a  sac  in  the  fascia  which  contains  smooth  fluid  resem- 
bling syno\da.  Bursce  are  found  where  much  pressure  or  friction 
occurs  between  different  structures.  They  act  like  water-cushions, 
thus  saving  the  tissues  from  bruising  or  rubbing.  The  largest  sub- 
cutaneous bursa  is  in  the  superficial  fascia  in  front  of  the  patella. 
It  is  called  the  prepatellar  bursa  (Fig.  62). 

Surgical  note. — When  the  prepatellar  bursa  becomes  inflamed 
and  enlarged,  it  forms  "housemaid's  knee." 

Sometimes  bursas  are  placed  underneath  tendons  or  between 
muscles,  and  these  deep  ones  may  communicate  with  joints.  There 
is  a  large  one  between  the  gluteus  maximus  and  the  tuberosity  of  the 
ischium,  and  another  between  the  same  muscle  and  the  great 
trochanter. 

Note. — The  transversalis  and  pelvic  fasciae  are  described  on  pages  93 
and  103. 

MUSCLES,  THEIR  IMPORTANCE. 

The  growth  of  bone  and  fashioning  of  joints  has  but  prepared  the 
way  for  more  important  ends  to  be  accomplished. 

The  head  and  trunk  protect  and  support  the  vital  organs,  but 
the  food  and  the  air  upon  which  their  life  depends  come  only  through 


78 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES, 


the  aid  of  those  constant  workers,  the  muscles.  All  motion  of  any 
sort  in  the  body,  whether  conscious  or  unconscious,  is  due  to  their 
action.  If  the  motion  is  voluntary  it  is  due  to  muscles  which  are 
controlled  by  the  will,  or  voluntary  muscles.  Muscles  which  cannot 
be  controlled  by  the  will  are  involuntary;  they  are  found  in  the  inter- 
nal organs  of  the  body,  or  the  viscera,  and  in  the  coats  of  the  vessels. 

All  other  muscles  are  volun- 
tary, and  since  they  are  at- 
tached to  bones  they  are  called 
skeletal  muscles. 

Note.— The  general  appear- 
ance of  muscle  tissue  may  be 
learned  from  specimens  obtained 
in  markets,  and  almost  all  of  the 
various  shapes  may  be  studied  in 
the  domestic  fowl. 

STRUCTURE  OF  MUSCLES. 

Muscles  consist  chiefly  of 
collections  of  red  fibers,  each 
fiber  composed  of  little  bun- 
dles of  muscle-cells.  All  of 
these  are  wrapped  in  connec- 
tive tissue,  bound  together 
and  enclosed  in  a  sheath. 

Examining  a  muscle  with  care, 
we  can  strip  off  the  sheath  of  con- 
nective tissue  (epi-mysium) ,  and  we 
shall  find  that  it  sends  layers  down 
into  the  muscle  to  form  septa  or 
partitions  (peri-mysium)  enclosing 
the  bundles  (or  fasciculi)  of  which 
the  muscle  is  made  up. 
With  the  aid  of  the  microscope  the  fiber  cells  which  compose  the  bundles 
are  revealed,  surrounded  by  still  more  delicate  connective  tissue  (endo-mysium). 
Also,  under  the  microscope  the  fiber  cells  of  voluntary  muscle  tissue  appear 
striped,  consequently  voluntary  muscle  is  said  to  be  striped  or  striated.  In- 
voluntary fiber  cells  are  plain — involuntary  muscle  is  unstriped  or  non-striated. 
This  sort  of  muscle  is  found  in  internal  organs,  whose  work  must  go  on  con- 
tinually without  our  conscious  supervision. 

Exception. — The  heart:  which  acts  whether  we  will  or  not,  although  its 
muscle  is  striated. 


Fig.     67. 
Muscles. 
(Holden.) 


-Showing    Lxtremities    of 
Tendon.     5,  Aponeurosis. — 


STRUCTURE    OF    MUSCLES. 


79 


In  most  cases  the  connective  tissue  is  prolonged  beyond  the  mus- 
cle into  a  white  cord  or  band  called  a  tendon,  if  the  muscle  is  long  and 
thick;  or  into  a  broad  thin  layer  called  an  aponeurosis  if  the  muscle  is 
flat;  and  by  these  tendons  and  aponeuroses  the  muscles  are  attached 
to  bones  and  other  organs.  Sometimes  the  red  fibers  are  attached 
directly  to  the  parts  which  they  move,  but  in  by  far  the  greater  num- 
ber the  tendons  are  conspicuous  (Fig.  67). 

Muscles  are  described  as 
consisting  of  a  body  and  two  ex- 
tremities; the  body  or  belly  being 
the  red  contracting  part  which 
swells  in  action,  while  tendons 
(which  are  possessed  by  most  of 
the  muscles)  are  simply  strong 
white  fibrous  bands  having  no 
power  to  contract  and  no  elas- 
ticity. This  is  equally  true  of 
the  aponeuroses. 

The  attachments  of  the  ex- 
tremities are  spoken  of  as  the 
origin  and  the  insertion.  The 
extremity  which  is  stationary 
while  the  other  end  moves,  is 
the  origin;  the  end  which  moves 
with  the  organ  attached  to  it,  is 
the  insertion.  The  insertion  is 
always  pulled  toward  the  origin 
when  the  muscle  contracts. 

THE  MUSCLES  OF  THE  TRUNK.  ^ 
Intercostal    muscles. — In 

two  sets,  the  internal  and  the 
external,  which  occupy  the  in- 
tercostal spaces.  The  fibers  run  obliquely  from  rib  to  rib,  the  in- 
ternal fibers  running  upward  and  forward,  the  external  fibers  running 
downward  and  forward. 

Action. — They  move  the  ribs  up  and  down  in  breathing  and  the 
various  acts  associated  with  it. 

'  Many  skeletal  muscles  have  their  origin  partly  from  the  deep  fascia  covering  them. 
The  bony  origins  only  are  given  here,  as  a  rule. 


Fig.  68. — Intercostal  Muscles. — (Morris.) 


8o 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


Principal  Muscles  of  the  Back. 

In  the  skeleton  a  broad  groove  exists  on  either  side  of  the 
spinous  processes,  which  is  filled  in  its  whole  extent  with  many 
vertical  muscles  of  different  lengths,  the  use  of  which  is  to  hold 

the  spine  in  the  erect  position;  also  they 
assist  to  move  it  in  various  directions. 

The  erector  spinae  is  the  name  given 
to  this  large  group,  which  is  bound  down 
in  its  place  by  a  thin  layer  of  fibrous  tissue 
called  the  vertebral  aponeurosis.  This 
muscle  group  extends  from  the  skull  to 
the  lower  part  of  the  sacrum  (Fig.  69). 

The  action  is  most  easily  seen  in  the 
lumbar  and  dorsal  regions,  where  it  is  not 
deeply  covered  with  other  muscles. 

Nerves. — Posterior  spinal. 

The  latissimus  dorsi  (broadest  of  the 
back,  Fig.  70). — This  muscle  covers  most 
of  the  erector  spinae  and  a  great  portion 
of  the  back  of  the  trunk. 

Origin. — The  spinous  processes,  from 
the  sixth  thoracic  down  to  the  end  of  the 
column. 

Also  the  crest  of  the  ilium  and  a  few  fibers 
from  the  inferior  angle  of  the  scapula. 

Insertion. — The  crest  of  the  lesser 
tubercle  of  the  humerus. 

Action, — ^Principally  to  pull  the  arm 
backward  and  keep  the  scapula  or  shoulder- 
blade  close  to  the  chest;  brought  prominently  into  use  in  rowing  a 
boat  or  when  the  body  is  suspended  by  the  hands  and  an  effort  is 
made  to  draw  it  up. 

Nerves. — Posterior  spinal  and  long  subscapular. 

Muscles  of  the  Back  of  the  Neck. 

These  muscles  move  the  head  and  neck.  Only  the  most  im- 
portant are  here  described. 

The  splenius. — This  muscle  is  in  two  portions,  the  splenius  of  the  head 
(capitis)  and  the  splenius  of  the  neck  (cervicis)  (Fig.  69). 


-The    Figures 
Refer  to  the  Spinal  Group 

AND    the    QuADRATUS    LuM- 

BORUM. — (Potter's  Anatomy.) 


MUSCLES    OF    THE    NECK. 


8r 


Origin. — The  spinous  processes  of  the  last  cervical  and  first  six  thoracic 
vertebras.  Insertion. — Partly  upon  occipital  and  mastoid  bones  {splenius  cap- 
itis) and  partly  upon  the  transverse  processes  of  the  upper  vertebrae  {splenius 
cervicis) . 


Fig.  70. — Superficial  amp  Middle  Muscular  Layers  of  the  Posterior  Aspect 
OF  THE  Trunk. — Holden.) 
I,  Trapezius;  2,  latissimus  dorsi;  3,  aponeurosis;  4,  5,  6,  8,  19,  20,  different  portions 
of  latissimus  dorsi;  9-12,  deep  muscles;  13,  stemo-mastoid;  14,  splenius;  15,  elevator 
of  scapula;  16,  infraspinatus;  17,  teres  minor;  7,  18,  teres  major;  21,  portion  of  anterior 
serratus;  22,  23,  abdominal  muscles;  24,  25,  gluteus  maximus;  26-30,  deep  muscles; 
31,  deltoid;  32,  triceps. 

Action. — The  muscle  of  one  side  alone  will  rotate  the  head,  tw^isting  the 
neck.  The  muscles  of  both  sides  acting  together  simply  pull  the  head  backward 
or  extend  it  and  the  neck. 

Nerves. — Posterior  cervical. 
6 


82  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

The  trapezius  covers  the  other  muscles  of  the  back  of  the 
neck,  and  also  the  upper  portion  of  the  latissimus  dorsi.  It  is  one 
of  the  largest  muscles  in  the  body  (Fig.  70).  The  two  muscles, 
right  and  left  together  make  a  large  diamond-shaped  sheet. 

Origin. — The  occipital  bone,  the  ligamentum  nuchae,  and  the 
spinous  processes  of  the  thoracic  vertebrae.  Insertion. — ^The  spine 
of  the  scapula  and  lateral  third  of  the  clavicula. 

Action. — With  the  shoulders  stationary  the  trapezius  acts  upon 
the  head  to  pull  it  backward  or  sideways.  With  the  head  stationary 
it  can  elevate  the  shoulder-girdle  and  the  whole  upper  extremity 
with  it.  Both  muscles  together  can  draw  the  shoulders  back.  If 
the  hands  grasp  a  bar  above  the  head  these  muscles  will  assist  to 
draw  the  body  up.  The  largest  two  of  the  "climbing  muscles" 
are  the  latissimus  dorsi  and  the  trapezius. 

Nerves. — Cervical,  and  spinal  accessory. 

Note. — Observe  in  the  illustration  its  tendinous  area,  which  remains  flat 
during  action  of  the  muscle. 

Clinical  Note. — Spasmodic  action  of  the  trapezius  is  often 
the  cause  of  wry-neck,  or  torticollis,  and  this  may  be  increased  by 
spasm  of  the  splenius. 

Muscles  or  Head,  and  Front  and  Side  of  the  Neck  (Fig.  71). 

The  muscles  of  expression  are  those  of  the  scalp  and  face. 
They  are  closely  connected  with  the  under  surface  of  the  skin,  or 
with  each  other;  they  have  no  deep  fascia  over  them,  and  therefore 
their  slightest  contraction  is  shown  on  the  face,  thus  varying  the 
movements  and  lines  of  expression. 

Epicranial  muscle.— On  the  forehead  and  the  top  and  back 
of  the  head — a  broad  thin  muscle  made  up  of  two  distinct  parts 
with  an  aponeurosis  between  them.  The  posterior  part  is  the 
occipitalis,  taking  origin  from  the  curved  line  of  the  occipital 
bone  and  ending  in  the  aponeurosis  on  the  top  of  the  head.  The 
anterior  part  is  the  frontalis,  having  origin  in  the  aponeurosis, 
and  passing  down  over  the  forehead  to  the  insertion  in  the  tissues 
of  the  eyebrows. 

Action. — ^Principally  to  lift  the  eyebrows,  producing  the  trans- 
verse wrinkles  across  the  forehead  which  express  surprise.  The 
skin  is  closely  connected  with  this  double  muscle  in  its  whole  length, 


THE    EPICR.A.NL\L    MUSCLE. 


83 


SO  that  contraction  causes  movement  of  the  scalp.  (Some  people 
can  move  the  scalp  backward  and  forward  by  contracting  the  two 
portions  alternately). 


Epicranial 
aponeurosis 


Frontalis 


Fig.  71. — Muscles  of  tiie  Head  and  Neck. — (Morris.) 


The  aponeurosis  extends  in  a  thin  layer  at  the  side  over  the  temporal  region, 
giving  origin  to  certain  small  muscles  which  move  the  ear.  The  scalp  and  ear 
usually  move  together. 

Nerve. — Seventh  cranial  {or  facial). 


§4  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES, 

Orbicularis  oculi. — The  ring-like  muscle  of  the  eyelid.  It  is 
attached  to  the  medial  border  of  the  orbit.  Some  of  its  fibers  are  in 
tjjg  \{^ — the  palpebral  portion — while  others  surround  the  lids  like  a 
broad  flat  ribbon,  forming  the  circular  or  orbilal  portion,  and  bearing 
the  eyebrows  (Fig.  71). 

Action. — When  the  palpebral  fibers  contract  the  lids  cover  the 
eyeballs  lightly;  when  the  circular  fibers  contract  the  lids  are  pressed 
against  the  ball. 

Nerve. — Seventh  cranial. 

Levator  palpebrag  (elevator  of  the  eyelid). — Within  the  orbit. 
Origin. — At  the  apex  of  the  orbit.     Insertion. — In  the  upper  lid. 

Action. — It  lifts  the  lid  and  opens  the  eye. 

Nerve. — Seventh  cranial. 

Corrugator. — The  muscle  which  wrinkles  the  eyebrow.  Origin. 
— The  frontal  bone.     Insertion. — The  under  surface  of  eyebrow. 

Action. — It  draws  the  brows  downward  and  inward  toward 
each  other;  it  is  the  frowning  muscle. 

Nerve. — Seventh  cranial. 

Orbicularis  oris  (ring  muscle  of  the  mouth). — Surrounds  the 
opening  of  the  mouth,  constituting  the  larger  portion  of  the  lips. 
The  fibers  have  only  one  bony  attachment — below  the  septum  of 
the  nose. 

Action. — It  closes  the  mouth. 

The  lips  themselves  are  moved  in  various  ways  by  muscles 
above  and  below  them — the  elevators  and  depressors  of  the  lips 
(all  supplied  by  the  seventh  cranial  nerve). 

Special  points. — Most  of  the  changes  in  the  expression  of  the  face  are 
caused  by  the  action  of  the  ring  imiscles  and  of  those  which  are  attached  to  them. 
For  example,  the  lifting  of  the  eyelids  by  the  frontalis  expresses  surprise.  The 
wrinkling  of  the  brows  by  the  corrugators  speaks  disapproval  or  bewilderment. 
The  risorius,  or  laughing  muscle,  draws  the  corners  of  the  mouth  outward.  The 
sneering  muscle  lifts  the  nostril,  and  lip  together.  Pleasure  is  expressed  by  the 
lifting  of  the  angles  of  the  lips  upward  and  outward,  while  grief  depresses  them. 
(There  are  but  three  of  the  depressors,  or  grieving  muscles,  on  each  side,  and 
six  for  the  manifestation  of  happier  feelings.) 

Muscles  of  Mastication,  Five  in  Number 

The  temporal  muscle. — Occupying  the  entire  temporal  fossa. 
Origin. — The  floor  of  the  fossa,  and  the  temporal  fascia  covering 
it.     Insertion. — The  coronoid  process  of  the  mandible. 


MUSCLES    OF    MASTICATION. 


85 


Action. — It  closes  the  mouth  and  draws  the  mandible  or  lower 
jaw-bone  backward. 

Nerve. — Fifth  cranial  (or  tri-facial). 

The  masseter. — At  the  side  of  the  face  (Fig.  73).  Origin. — 
The  zygomatic  arch.  Insertion. — The  lateral  surface  of  the  ramus 
of  the  mandible. 

Action. — It  closes  the  mouth  and  moves  the  jaw  forward  slightly. 

Nerve. — Fifth  cranial. 


Temporal 


Buccinator 


Fig.  72. — The  Temporal  Muscle. — (Morris.) 


The  internal  pterygoid. — In  the  infra-temporal  fossa  covered  by  the  ramus 
of  the  mandible  on  which  it  is  inserted. 

Action. — It  closes  the  mouth  and  moves  the  ']a.w  forward  and  sideways. 

External  pterygoid. — Also  in  the  infra-temporal  fossa  and  inserted  on  the 
mandible. 

Action. — It  moves  the  jaw  forward  and  sideways. 

Nerve. — Fifth  cranial. 

Buccinator. — Origin,  from  both  the  maxilla  and  the  mandible  on  the 
alveolar  borders.  The  fibers  approach  each  other,  interlacing  and  running 
forward,  and  some  of  them  join  the  lip  muscles,  constituting  the  insertion 
(Fig.  72). 


86 


ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 


Action. — It  helps  to  close  the  mouth,  and  keeps  the  food  between  the  teeth 
during  the  act  of  mastication. 

Nerves. — Fifth  and  seventh  cranial. 

By  the  action  of  the  first  four  muscles  the  food  is  divided  and 
crushed,  and  also  ground;  the  external  pterygoid  is  especially  a 
grinding  muscle.  The  function  or  use  of  these  four  would  be  some- 
what limited  without  the  aid  of  the  buccinator. 

Muscles  in  the  Front  of  the  Neck. 

The  ribbon  muscles,  thin  and  fiat,  connecting  the  larynx  and 
hyoid  bone  above,  with  the  sternum,  rib,  and  clavicula  below. 


Fig.  73. — Muscles  in  Front  or  the  Neck. 
I,  2,  3,  Digastric  muscle;  4,  stylo-hyoid;  5,  mylo-hyoid;  6,  hyo-glossus;  7,  8,  9, 
sterno-mastoid;  10,  11,  12,  13,  14,  ribbon  muscles;  15,  pharynx;  16,  occipitalis;  17,  ear 
muscles;  18,  trapezius;  19,  20,  splenius;  21,  levator  scapulae;  22,  23,  scalene;  24,  deltoid; 
25,  pectoralis  major;  26,  right  platysma;  27,  28,  lip  muscles;  29,  masseter;  30,  buccina- 
tor.— (From  Holden.) 

They  are  the  stemo-hyoid,  the  stemo-thyroid,  and  the  otno-hyoid  (a 

double-bellied  muscle,  with  an  intervening  tendon,  the  inferior  belly  being 
attached  to  the  upper  border  of  the  scapula,  the  superior  belly  to  the  hyoid  bone, 
while  the  tendon  between  them  glides  through  a  loop  of  fascia  attached  to  the 
clavicula). 


MUSCLES    OF    THE    NECK.  87 

Action  of  the  three  muscles. — They  draw  the  hyoid  bone  and 
the  larynx  downward,  and  steady  them. 
Nerves. — Ninth  cranial,  or  hypoglossal. 
The  digastric  is  another  double-bellied  muscle  (Fig.  73). 

The  posterior  belly  is  attached  to  the  mastoid  process  (medial  surface) ;  the 
anterior  belly  to  the  under  surface  of  the  mandible  close  to  the  symphysis.  The 
intervening  tendon  glides  through  a  loop  of  fascia  connected  with  the  hyoid  bone. 

Action. — It  draws  the  mandible  downward,  and  opens  the 
mouth.  It  is  assisted  by  some  other  short  muscles  connecting  the 
mandible  to  the  hyoid  bone. 

Nerves. — Sei'enth  cranial  and  fifth  cranial. 

The  mylo-hyoid  (Fig.  73)  is  a  flat  muscle  which  forms  the  floor 
of  the  mouth,  being  attached  by  one  border  to  the  inner  surface  of 
the  body  of  the  mandible,  and  by  the  other  to  the  hyoid  bone,  which, 
it  will  be  remembered,  is  on  a  level  with  the  mandible. 

Action. — It  can  draw  the  hyoid  bone  forward  in  the  act  of 
swallowing,  thus  keeping  the  larynx  out  of  the  way  of  the  food. 

Nerves. — Seventh  cranial  {and  cervical). 

The  platysma. — As  the  muscles  of  the  back  and  side  of  the  neck  are  covered 
by  the  trapezius,  so  those  of  the  front  and  side  are  covered  by  the  platysma, 
which  is  a  broad  thin  sheet  of  muscular  fibers  attached  above  to  the  mandible 
and  the  fascia  of  the  side  of  the  face,  and  below  to  the  deep  fascia  on  the  front 
of  the  shoulder  (Fig.  71).  Like  the  face  muscles,  it  is  not  covered  by  deep 
fascia,  and  since  it  moves  the  skin,  it  is  like  them  a  muscle  of  expression.  It 
draws  the  angle  of  the  mouth  downward,  and  strong  contractions  of  the  muscle 
assist  in  causing  an  appearance  as  of  one  in  a  "great  rage."  The  action  of 
this  muscle  in  grazing  animals  is  displayed  when  used  to  shake  off  insects 
which  alight  upon  the  skin  of  the  neck. 

The  sterno-cleido-mastoid  (Figs.  71,  73)  is  the  most  conspicu- 
ous muscle  in  the  side  of  the  neck.  Origin. — By  two  divisions,  one 
on  the  sternum  (sternal,  or  medial  origin),  the  other  on  the  clavicula 
(clavicular,  or  lateral  origin).  Insertion. — The  mastoid  process 
and  upper  curved  line  of  the  occipital  bone. 

Action.— Principally  to  pull  the  mastoid  process  toward  the 
sternum  and  clavicula.  If  the  righl  muscle  contracts  the  right 
mastoid  process  comes  downward  and  forward  and  the  chin  turns 
upward  to  the  left.  If  the  left  muscle  contracts  the  left  mastoid  is 
pulled  downward  and  forward  and  the  chin  goes  upward  to  the  right. 
Both  muscles  together  simply  bend  the  head  forward,  or  flex  it. 

Nerves. — Spinal  accessory  {and  cervical). 


S8  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

Clinical  note. — The  sterno-mastoid  is  another  muscle  which  is  sometimes 
the  seat  of  spasmodic  contractions,  causing  wry-neck,  or  torticollis. 

Levator  scapulae. — The  elevator  of  the  scapula  is  an  important  muscle 
in  the  side  of  the  neck.  Origin. — The  upper  three  or  four  transverse  processes. 
Insertion. — The  medial  angle  of  the  scapula. 

Nerves. — Cervical. 


Fig.  74. — Anterior  Surface  of  the  Abdominal  Wall. 
I)  2,  3,  7,  Pectoralis  major;  4,  external  oblique;  5,  serratus  anterior;  6,  latissimus- 
dorsi;  8,  xiphoid  appendix;  9,  9,  15,  aponeurosis  of  ext.  oblique;  10,  14,  linea  alba;  11, 
umbilicus;  12,  transverse  lines  of  aponeurosis;  13,  13,  subcutaneous  abdominal  ring; 
16,  17,  18,  19,  refer  to  muscles  of  neck;  20,  deltoid. — (Gould's  Dictionary.)  Lower 
border  of  aponeurosis  is  inguinal  ligament. 


THE  ABDOMINAL  WALL. 

The  abdominal  wall  has  no  bones  except  the  lumbar  vertebrae, 
being  mostly  muscular  and  aponeurotic.  Each  lateral  half  is  com- 
posed of  one  vertical  muscle  in  front,  next  to  the  median  line;^ 


ABDOMINAL    MUSCLES. 


89 


another  in  the  back,  next  to  the  spinal  column;  and  three  well- 
developed  layers  having  fibers  of  different  directions,  at  the  sides. 

Rectus  abdominis  (Fig.  75). — This  is  the  vertical  muscle  in 
front.  Origin. — The  body  of  the  pubes.  Insertion.— The  ensi- 
form  appendix  and  the  cartilages  of  the  fifth,  sixth,  and  seventh  ribs. 
It  is  therefore  narrow  below  and  broad  above,  and  its  outer  border 
is  curved  from  the  seventh  rib  down  to  the  pubes.  This  is 
indicated  in  the  fascia  over  the  muscle  by  a  distinct  line  called  the 
linea  semilunaris  {semilunar  line). 


Fig.  75. — Internal  Oblique  and  Transverse  Muscles. 
I,  Rectus  abdominis;  2,  2,  3,  3,  internal  oblique  and  cut  edge  of  its  aponeurosis; 
4,  4,  cut  edge  external  oblique;  5,  5,  spermatic  cords;  6,  aponeurosis  ext.  oblique  turned 
down;  7,  rectus,  upper  part  removed;  8,  8,  9,  transversus  muscle;  10,  umbilicus;  11,  12, 
linea  alba;  13,  serratus  anterior;  14,  15,  cut  edge  latissimus  dorsi;  17,  17,  external  inter- 
costal; 19,  cut  edge  external  oblique. — (Gould's  Dictionary.) 


Action. — It  compresses  the  abdominal  organs. 

Nerves. — Lower  thoracic. 

Quadratus  lumborum. — This  is  the  vertical  muscle  at  the 
back  (Fig.  69).  Origin. — The  crest  of  the  ilium.  Insertion.— 
The  lowest  rib  and  transverse  processes  of  the  lumbar  vertebrae. 
It  occupies  the  space  at  the  back  of  the  trunk  between  the  thorax  and 
pelvis,  being  covered  by  the  erector  spinge  and  latissimus  dorsi. 


90 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


Action. — It  draws  the  rib  down  and  the  spine  to  one  side — 
lateral  flexion  of  the  trunk. 

Nerves. — Lower  thoracic. 

The  three  layers  at  the  side  and  front  consist  of  the  obliquus 
externus  or  external  oblique;  the  obliquus  internus,  or  internal 
oblique;  and  the  transversus  muscles.  They  occupy  the  space 
between  the  eight  lower  ribs  above,  and  the  ilium  and  pubes  below. 
Being  broad  and  fiat  they  do  not  possess  tendons  of  the  usual  kind, 
but  many  of  their  muscle  fibers  terminate  in  layers  of  white  fibrous 
tissue  called  aponeuroses,  which  continue  to  the  median  line,  there 
blending  with  the  layers  from  the  opposite  side.  This  produces  a 
firm  interlacing  of  white  fibers  called  the  linea  alba  or  white  line, 
stretched  between  the  ensiform  appendix  above  and  the  body  of 
the  pubes  below.  It  is  a  very  strong  and  important  line,  through 
which,  a  little  below  the  middle,  the  umbilical  cord  passes  in  the  fetus. 
This  point  in  the  linea  alba  is  indicated  by  the  umbilicus,  or  navel. 

The  external  oblique  (Fig.  74)  is  the  outermost  of  the  three 
layers.  Origin. — The  lower  eight  ribs.  Direction  of  fibers,  down- 
ward and  forv/ard.  Insertion. — Some  fibers  on  the  crest  of  the 
ilium;  others  in  an  aponeurosis  which  passes  to  the  linea  alba. 

Nerves. — Lower  thoracic. 

Special  point. — The  lower  border  of  the  aponeurosis  of  this  muscle  between 
the  spine  of  the  iUum  and  the  spine  of  the  pubes  is  firm  and  unyielding,  easily 
felt,  and  important  to  be  recognized;  it  is  called  the  inguinal  ligament  (or 
Pouparfs  ligament) . 

The  internal  oblique  (Fig.  75)  lies  underneath  the  external 
oblique.  Origin. — The  lumbar  fascia,  crest  of  the  ilium,  and  lateral 
half  of  the  inguinal  ligament.  Direction  of  fibers,  upward  and  for- 
ward. Insertion. — Some  fibers  on  the  lower  four  ribs,  others  in 
the  linea  alba,  and  the  lowest  ones  on  the  crest  of  the  pubes. 

Nerves. — Lower  thoracic  and  ilio-inguinal. 

The  transversus  (Fig.  75)  is  the  innermost  of  the  three  layers. 
Origin. — The  lower  six  ribs,  the  lumbar  fascia,  crest  of  the  ilium, 
and  lateral  half  of  the  inguinal  ligament.  Direction  of  fibers,  trans- 
versely across  the  side  of  the  abdomen,  toward  the  front.  Inser- 
tion.— In  the  linea  alba,  and  the  crest  of  the  pubes.  On  the  pubes 
it  is  blended  with  that  part  of  the  internal  oblique  which  is  attached 
to  the  same  bone,  making  the  conjoined  tendon. 

Nerve. — Lower  thoracic. 


SHEATH    OF    RECTUS    ABDOMINIS.       DIAPHRAGM. 


91 


Action,  of  the  three  broad  muscles. — They  compress  the  ab- 
dominal viscera  and  expel  the  contents  of  those  which  are  hollow. 

The  fibers  from  the  inguinal  ligament,  of  both  internal  oblique  and  transversus 
muscles,  arch  downward  to  the  pubes. 

Sheath  of  the  Rectus  Abdominis  (Figs.  74,  75). 

In  the  lower  fourth  of  the  linea  semilunaris,  the  entire  thickness 
is  continued  forward  as  one  layer  in  front  of  the  muscles.  In  the 
upper  three-fourths  the  linea  semilunaris  divides  into  two  layers 
which  meet  again  in  the  linea  alba;  thus  a  compartment  is  formed 
to  be  occupied  by  the  rectus  muscle. 

This  is  called  the  sheath  of  the  rectus,  with  its  anterior  and 
posterior  layers,  the  anterior  layer  being  thickest  and  strongest  in 
the  lower  part  where  the  greatest  strain  would  be  brought  upon  it. 

Lineae  transversse  (transverse  lines). — At  three  different  levels 
above  the  umbilicus  the  anterior  layer  of  the  sheath  is  held  down 
to  the  rectus  muscle  by  fibers  forming  three  transverse  lines. 

Note. — The  location  of  all  these  markings — the  semilunar  line,  the  white 
line,  and  the  three  transverse — may  be  seen  on  the  surface  of  the  body  during 
the  action  of  the  muscles;  and  in  a  piece  of  statuary  representing  the  trunk  they 
should  be  plainly  indicated  (Fig.  74). 

Roof  of  the  Abdomen. 

The  roof  of  the  abdomen 
is  the  diaphragm;  it  has  no 
floor  of  its  own,  the  pelvic 
floor  serving  for  both  cavities 
(page  103). 

The  diaphragm. — This  is 
a  broad,  thin,  dome-shaped 
muscle  separating  the  abdom- 
inal and  thoracic  cavities. 
The  central  portion  is  apo- 
neurotic, serving  for  the  in- 
sertion of  the  remaining  or 
muscular  portion. 

Origin. — a.  By  two  vertical  bundles  at  the  sides  of  the  lumbar 
vertebrce.  These  vertical  portions  are  the  crura  of  the  diaphragm. 
Their  fibers  turn  forward,  crossing  and  interlacing  before  they  end 


Fig.  76. — The  Diaphragm. 

Dotted  lines  indicate  descent  in  contraction. 

— (Holden.) 


92 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


in  the  central  tendon,  b.  From  arches  of  lumbar  fascia  and  the 
lower  boundary  of  the  thorax  (seventh  to  twelfth  ribs  and  xiphoid 
appendix). 

Insertion. — In  a  fiat  central  tendon,  shaped  like  a  clover  leaf, 
near  the  center  of  the  dome.  The  lateral  portion  arches  higher  than 
the  central,  forming  a  cupola  on  each  side. 

Action. — When  the  diaphragm  contracts  it  becomes  flattened, 
pressing  upon  the  abdominal  organs;  when  it  relaxes,  it  springs 
back  to  its 'dome-shape,  as  high  as  the  fourth  or  fifth  rib,  pushing 
gently  against  the  lungs. 

Nerve. — Phrenic. 


Fig.  77. — The  Diaphragm,  Inferior  Surface. 
I,  2,  3,  Tendinous  leaflets;  4,  muscle  fibers;  5,  6,  7,  tendinous  arches;  8,  10,  fibers 
arising  from  vertebrae;  11,  aorta — a  large  artery;  12,  esophagus,  leading  to  stomach;  13, 
opening  for  vena  cava. — (Potter's  Compend  of  Anatomy.) 

Special  points. — This  muscle  forms  the  floor  of  the  thorax,  and 
at  the  same  time  the  roof  of  the  abdomen  (convex  floor,  concave  roof). 
There  are  three  openings  in  it  at  the  back  part  for  the  passage  of  a 
large  artery  and  vein, — the  aorta  and  vena  cava,  and  the  esophagus. 

With  the  muscles  thus  far  described  the  walls  of  the  cavities  of 
the  trunk— dorsal  and  ventral — are  completed  (see  page  48). 

Interior  Abdominal  Muscles. 

The  psoas  major  and  iliacus. — These  are  two  muscles  within. 
the  abdomen  (on  the  posterior  wall)  which  pass  out  over  the  brim 
of  the  pelvis  into  the  thigh. 


ILIO-PSOAS. 


93 


Psoas  major.  Origin. — The  sides  of  the  lumbar  vertebrae. 
Insertion. — Trochanter  minor  of  the  femur. 

Iliacus.  Origin. — The  iliac  fossa.  Insertion. — With  the 
psoas  on  the  trochanter  minor  of  the  femur. 

Action. — -They  act  together  as  one  muscle,  the  ilio-psoas,  to 
flex  the  thigh,  at  the  same  time  rotating  it,  so  that  the  foot  turns 
outward. 

Nerves. — Lumbar  and  femoral. 


Fig.  78. — Abdominal  Muscles,  Interior. 
1-5,  Psoas  minor  and  major;  6,  attachment  of  psoas  major  to  trochanter  minor, 
7,  7,  8,  8,  iliacus;  9,  9,  cut  tendon  rectus  femoris;  10,  10,  obturator  externus;  11-13 
quadratus  lumborum;  14,  14,  transversus. — (Gould's  Dictionary.) 

Surgical  note. — Disease  of  the  lumbar  vertebrs  resulting  in  pus  forms 
psoas  abscess.  The  pus  often  follows  the  muscle  fibers  downward  and  appears 
below  the  inguinal  ligament. 

(The  psoas  minor  is  a  small  muscle  in  front  of  the  major.) 

The  transversalis  fascia  is  a  layer  of  loose  connective  tissue 
which  completely  lines  the  abdomen;  it  is  continuous  with  the 
iliac  fascia  on  the  iliacus  muscle  and  with  the  pelvic  fascia  below. 


CHAPTER  VII. 

MUSCLES  OF  THE  EXTREMITIES. 

The  muscles  of  the  extremities  are  frequently  named  for  their 
use,  and  they  may  all  be  grouped  according  to  their  action;  as 
flexors,  to  bend  the  joints  over  which  they  pass,  and  extensors  to 
straighten  them;  pronators  and  supinators;  abductors  smd adductors; 
and  rotators,  inward  or  outward.  Their  origins  are  not  only  from 
bones,  but  from  fascia,  and  the  fibrous  septa  between  them.  This 
is  true  of  most  muscles  to  some  extent,  but  particularly  so  in  the 
extremities. 

The  bony  attachments  only  are  given  here. 

MUSCLES  OF  THE  UPPER  EXTREMITY. 

Shoulder  Muscles. 

Supraspinatus. — On  the  dorsal  surface  of  the  scapula.  Origin. 
— The  supraspinous  fossa,  the  tendon  passing  over  the  head  of  the 
humerus  to  the  insertion  on  the  top  of  the  greater  tubercle. 

Action. — It  lifts  the  arm  away  from  body  (abduction). 

Infraspinatus. — Also  on  the  dorsal  surface  of  the  scapula. 
Origin. — ^The  infraspinous  fossa.  Insertion. — The  greater  tu- 
bercle of  the  humerus  (below  the  supraspinatus). 

Action. — It  rotates  humerus  outward  (the  palm  turns  forward). 

Nerve,  both  muscles. — Suprascapular. 

Teres  minor.  Origin. — The  axillary  border  of  the  scapula.  Insertion. — 
The  greater  tubercle,  just  below  the  infraspinatus. 

Action. — It  rotates  humerus  outward  {palm  turns  forward). 
Nerve. — Axillary. 

Teres  major.  Origin. — Near  the  inferior  angle  of  the  scapula  (on  axillary 
border).  Insertion. — The  shaft  of  the  humerus  (crest  of  lesser  tubercle), 
joining  the  tendon  of  the  latissimus  dorsi  and  acting  with  it  (Fig.  79) . 

Action. — It  draws  the  arm  backward,  and  rotates  it  inward  (the- palm  turns 
backward). 

Nerve. — Subscapular  {lower) . 

94 


MUSCLES    OF    THE    SHOULDER. 


95 


Subscapularis  (Fig.  8i).  Origin. — The  subscapular  fossa. 
Insertion. — The  lesser  tubercle  of  the  humerus. 

Action. — It  holds  head  of  humerus  in  place  and  rotates  it  in- 
ward (the  palm  turns  backward). 

The  deltoid  (Fig.  80).— Is 
triangular  in  shape  and  forms 
a  sort  of  cap  over  the  shoulder- 
joint.  Origin. — The  spine 
and  acromion  of  the  scapula, 
and  the  lateral  portion  of  the 
clavicula.  Insertion. — The 
lateral  surface  of  the  humerus 
at  the  middle  of  the  shaft,  on 
the  deltoid  tuberosity. 

Action. — Principally  to 
elevate  the  humerus  to  a  hori- 
zontal position  (acting  with 
the  supraspinatus,  an  abductor 
of  the  arm). 

Nerve. — Axillary. 

The    serratus     anterior 

(Figs.  70,  80). — A  large  flat 
and  important  muscle  which 
lies  between  the  scapula  and 
the  thorax.  Origin. — By 
separate  slips  from  eight  ribs, 
on  the  front  and  side  of  the 
thorax.  Insertion. — The 
vertebral  border  of  the  scapula. 
It  lies  close  to  the  side  of  the 
thorax,  covering  a  considera- 
ble portion  of  the  ribs  and 
intercostal  muscles. 

Three  actions. — It  holds  the  scapula  firmly  in  place  and  pulls 
it  forward,  thus  pushing  the  arm  ahead.  If  the  shoulders  are  held 
firmly  it  can  elevate  the  ribs,  assisting  inspiration.  It  sustains 
the  weight  of  the  body  when  resting  upon  hands  and  knees,  as  in 
creeping. 

Nerve. — Long  thoracic  or  external  respiratory. 


Fig.  79. — Muscles  of  the  Shoulder. 
I,  2,  3,  4,  5,  Triceps;  6,  attachment  to 
olecranon;  7,  anconeus;  8,  8,  g,  deltoid  (por- 
tion removed);  10,  supraspinatus;  11,  infra- 
spinatus; 12,  13,  two  extremities  of  teres 
minor  (intervening  portion  removed);  14, 
teres  major;  15,  latissimus  dorsi;  16,  17,  18, 
1 9,  musclesof  forearm. —  (Gould's  Dictionary.) 


c)6  anatomy  and  physiology  for  nurses. 

Breast  Muscles. 

Pectoralis  major.  Origin. — Clavicular  portion,  on  the  sternal 
end  of  the  clavicula;  sternal  portion,  on  the  surface  of  the  sternum 
and  on  six  upper  ribs.  Insertion. — By  a  broad  strong  tendon 
on  the  shaft  of  the  humerus,  on  the  crest  of  the  greater  tubercle. 
Figs.  74,  80. 


iff 


9-1 


—13 


4-i^' 


I 


as 


10  n 

Fig.  80. — Muscles  of  Anterior  Aspect  of  Thorax. 
1-5,  Pectoralis  major;  6,  9,  pectoralis  minor;  7,  subclavius;  8,  deltoid;  10,  anterior 
portion  of  anterior  serratus;  11,  external  oblique;  12, 13,  latissimus  dorsi;  14,  teres  major. 
— (Gould's  Dictionary.) 

Action. — It  draws  the  arm  to  the  front  of  the  thorax,  opposing 
the  latissimus  dorsi;  thus  it  also  is  a  "rowing '"muscle. 

The  pectoralis  minor  is  entirely  covered  by  the  major. 

Origin. — Three  upper  ribs.  Insertion. — The  coracoid  process  of  the 
scapula.  Action. — It  pulls  the  shoulder  downward.  It  may  pull  ribs  upward 
in  labored  breathing  or  forced  inspiration. 

Nerves  of  both  muscles. — Anterior  thoracic. 

Note. — When  the  whole  body  is  drawn  upward  by  the  hands,  as 
when  hanging  from  a  trapeze,  the  two  pectorals,  the  trapezius  and  the 
latissimus  are  acting  together. 

The  subclavius  is  a  small  muscle  lying  in  the  subclavian  groove  between 
the  clavicle  and  first  rib.     It  may  elevate  the  ribs  or  depress  the  clavicle. 

Arm  Muscles. 

Anterior. 

Biceps    brachii  (a  two-headed  muscle).     Origin. — The  scapula: 
the  long  head  above  the  glenoid  fossa,  and  the  short  head  on  the 


MUSCLES    OF    THE  ARM. 


97 


coracoid  process.     Insertion. — By  one  tendon  on  the  tuberosity 
of  the  radius  (Fig.  8i). 

Action. — It  flexes  the  forearm  on  the  arm. 

Nerve. — Musculo-cutaneous. 


Note. — If  the  biceps  hrachii  begins  to  contract  while  the  hand  is  pronated, 
the  first  effect  would  be  to  pull  the  radial  tuberosity  around  and  place  the  hand 
in  the  supinated  position,  then  flexion 
would  follow;  in  other  words,  the  biceps 
may  act  as  both  a  supinator  and  flexor. 

The  coraco-brachialis. — A  smaller 
muscle,  close  to  the  biceps.  Origin. — 
The  tip  of  the  coracoid  process.  In- 
sertion.— The  shaft  of  humerus,  medial 
side,  opposite  the  deltoid. 

Action. — It  lifts  the  humerus  for- 
ward. 

Nerve. — Musculo-cutaneous. 

The  brachialis. — Is  underneath  the 
biceps.  Origin. — The  anterior  surface 
of  the  humerus.  Insertion. — The  tuber- 
cle of  the  ulna,  just  below  the  coronoid 
process. 

Action, — With  the  biceps  it  flexes 
the  forearm. 

Note. — This  is  a  broad  muscle  and 
covers  the  front  of  the  elbow-joint. 

Nerve.  —  Musculo-cutaneous  and 
radial. 

Arm  Muscles  (Fig.  79). 
Posterior. 
The  triceps  brachii  (a  three- 
headed  muscle).  Origin. — The 
long  head,  on  the  scapula,  just 
below  the  glenoid  fossa,;  the  medial 
and  lateral  heads  on  the  posterior 
surface  of  the  humerus,  separated 
by  the  groove  for  the  radial  nerve. 
Insertion. — The  (top  of  the) 
olecranon  process  of  the  ulna. 

Action. — It  extends  the  forearm 
Nerve. — Radial. 
7 


E.SALLE  S. 

Fig.  81. — Muscles  of  the  Arm. 
I,  2,  3,  5,  Biceps  and  bicipital  fascia; 
4,  attachment  of  biceps  to  tuberosity  of 
radius;  6,  coracobrachialis;  7,  8,  inser- 
tion of  pectoralis  major;  9,  latissimus 
dorsi  (insertion) ;  10,  teres  major;  11, 
subsca  pularis;  12,  brachialis;  i^,  14, 
two  heads  of  triceps. — (Holden.) 

(opposing  the  biceps). 


gS  ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 

Note. — The  back  of  the  triceps  is  covered  at  its  lower  portion  by  a  fibrous 
layer  (aponeurosis)  which  receives  many  of  the  muscular  fibers.  In  action, 
the  three  heads  swell  while  this  fibrous  layer  remains  flat. 


Muscles  of  the  Forearm. 
Anterior. 

The  superficial  flexors. — The  medial  epicondyle  of  the  humerus 

gives  origin  to  a  group  of  superficial  muscles  which  flex  the  wrist  and 
fingers  (Fig.  82). 

Flexor  carpi  radialis,  or  radial Jiexor  of  the  wrist.  Origin. — 
The  medial  epicondyle.  Insertion. — The  base  of  the  second 
metacarpal  bone  (that  of  the  index-finger). 

Nerve. — Median. 

Flexor  carpi  ulnaris,  or  ulnar  jiexor  of  the  wrist.  Origin. — 
The  medial  epicondyle  and  dorsal  border  of  the  ulna.  Insertion. — • 
The  base  of  the  fifth  metacarpal  bone. 

Action  of  the  two. — To  flex  the  wrist. 

Nerve. — Ulnar. 

Flexor  digitoriun  sublimis,  or  superficial  jiexor  of  the  fingers. 
Origin. — The  medial  epicondyle,  the  upper  extremity  of  the  ulna, 
and  the  shaft  of  the  radius  (the  three  long  bones).  Insertion. — 
By  four  tendons,  one  for  each  finger,  on  the  second  row  of  the 
phalanges. 

Action. — It  flexes  the  second  joints  of  the  fingers,  but  not  the 
finger-tips. 

Nerve. — Med  'an. 

Deep  flexors. — The  shafts  of  the  bones  give  origin  to  the  deep 
flexors  of  the  fingers  and  thumb,  which  act  upon  the  third  row  of 
the  phalanges. 

Flexor  digitorum  profundus,  or  deep  flexor  of  the  -fingers. — Is  underneath 
the  superficial  flexor.  Origin. — The  shaft  of  the  ulna.  Insertion. — By  four 
tendons,  on  the  third  or  last  row  of  phalanges. 

Action. — It  flexes  the  finger-tips. 

Note. — Since  the  tendons  of  the  superficial  flexor  stop  at  the  second 
phalanges,  while  those  of  the  deep  flexor  pass  to  the  third  phalanges,  there  is  a 
fissure  in  each  superficial  tendon  just  before  it  ends,  through  which  the  deep 
tendon  passes  forward  to  the  bone  of  the  finger-tip  (Fig.  82) . 

Nerves. — Median  and  ulnar. 

Flexor  poUicis  longus,  or  long  flexor  of  the  thumb. — Origin. — The  shaft  of 
the  radius  (under  flexor  sublimis).     Insertion. — The  last  phalanx  of  the  thumb. 


MUSCLES    OF    THE    FOREARM. 


99 


Fig.  82. — Muscles  of  the  Forearm. 
I,  2,  4,  4,  Muscles  of  arm;  3,  tendon 
of  insertion  of  oiceps;  6,  round  pronator; 
7,  radial  flexor  of  wrist;  8,  9,  palmaris 
longus;  10,  II,  ulnar  flexor  of  wrist;  12,  13, 
brachio-radialLs;  14-18,  muscles  and  ten- 
dons belonging  to  posterior  of  forearm; 
iQ,  19,  superficial  flexor  of  fingers;  20,  20, 
21,  21,  tendons  of  the  same,  showing 
fissure;  22,  22,  tendons  of  deep  flexor 
coming  through  fissure  to  reach  the  third 
row  of  phalangc-s. — (Holden.) 


Fig.  83. 


-Muscles  of  the  Forearm, 
Dorsal  Aspect. 


I,  Aponeurosis  of  triceps;  2,  upper  end 
of  brachio-radialis;  3,  4,  long  radial  exten- 
sor of  wrist;  5,  6,  short  radial  extensor  of 
wrist;  7,  8,  8,  9,  9,  extensors  of  thumb; 
10,  10,  annular  ligaments;  11, 12, 12,  com- 
mon extensors  of  fingers;  13,  14,  special 
extensors  for  index  and  little  fijigers;  15, 
16,  ulnar  extensor  of  wrist;  18,  ulnar 
flexor  of  wrist;  ig,  posterior  border  of 
ulna;  20,  olecranon  process  of  ulna;  21, 
medial  epicondyle. — (Holden.) 


lOO  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

Action. — It  flexes  the  tip  of  the  thumb. 
Nerve.— Ulnar. 

Note. — These  tendons  for  the  fingers  and  thumb  lie  in  the 
deep  groove  on  the  front  of  the  carpus.  Friction  between  them  is 
prevented  by  sheaths  of  synovial  membrane. — vaginal  synovial 
membranes. 

The  Two  Pronators,  the  Round  and  the  Square. 

Pronator  teres,  or  round  pronator  (Fig.  82). 

Origin. — The  medial  epicondyle,  and  a  small  slip  from  the 
ulna  (coronoid  process).  It  passes  across  to  the  lateral  side  of  the 
radius,  to  the  insertion  at  the  middle  of  the  shaft. 

Nerve. — Median. 

Pronator  quadratus,  or  square  pronator. 
Origin. — The  shaft  of  the  ulna.     Insertion. — The  shaft  of  the  radius.     It 
lies  just  above  the  wrist  and  underneath  the  long  muscles  (close  to  the  bones). 
Nerve. — Ulnar. 

Action  of  the  two  pronators. — They  rotate  the  radius  so  as  to 
turn  the  palm  downward  (or  backward). 

One  slender  muscle,  which  is  superficial  to  all,  is  the  palmaris  longus. 
It  arises  on  the  medial  epicondyle  and  is  attached  below  to  the  palmar  fascia 
to  keep  it  tense — a  tensor  of  the  palmar  fascia. 

Nerve. — Median. 

Note. — It  is  understood  that  the  muscles  arising  from  the  epicondyle  have 
a  common  tendon  of  origin. 

Practical  point. — Observe,  by  experimenting,  that  flexion  and  moderate 
pronation  are  naturally  performed  together,  and  are  associated  in  the  majority 
of  the  motions  which  are  required  of  the  upper  extremity. 

Muscles  of  the  Forearm  (Fig.  83). 
Posterior. 

The  lateral  epicondyle  of  the  humerus  and  the  ridges  above  it 
give  origin  to  the  muscles  which  extend  the  wrist  and  fingers. 

Extensor  carpi  radialis  longus,  or  long  radial  extensor  of  the 
wrist.  Origin. — Lateral  border  and  epicondyle  of  humerus. 
Insertion. — The  base  of  the  second  metacarpal  bone. 

Nerve. — Radial. 


THE    SUPINATOR    MUSCLES.  lOI 

Extensor  carpi  radialis  brevis,  or  short  radial  extensor.  Ori- 
gin.— The  lateral  epicondyle.  Insertion. — The  base  of  the  third 
metacarpal  bone. 

Nerve. — Deep  branch  of  radial. 

Extensor  carpi  ulnaris,  or  ulnar  extensor  of  the  wrist. — Origin. 
^The  lateral  epicondyle  and  dorsal  border  of  the  ulna.  Inser- 
tion.— The  base  of  the  fifth  metacarpal  bone. 

Action  of  the  three. — They  extend  the  wrist. 

Nerve.— Deep  branch  of  radial. 

Extensor  digitorum  communis,  or  common  extensor  of  the 
fingers.  Origin. — The  lateral  epicondyle.  Insertion. — By  four 
tendons,  on  the  second  and  third  rows  of  phalanges,  in  such  a  way 
that  it  can  extend  the  bones  of  either  row  separately  or  both  at  the 
same  time. 

The  little  finger  has  a  special  extensor  for  its  tip  (e.xiensor  minimi  digiti). 
The  index  finger  also  has  a  special  extensor  {extensor  indicis),  and  the  thumb 
has  three — two  for  its  phalanges,  and  one  for  its  metacarpal  bone.  By  forcibly 
extending  the  thumb  these  three  tendons  are  brought  into  view,  the  one  for  the 
tip  of  the  thumb  being  at  a  little  distance  from  the  other  two;  thus  they  bound 
a  little  hollow  which  has  been  called  the  "anatomic  snuff  box." 

Nerves  of  all. — Deep  branch  of  radial. 

The  Two  Supinators. 

The  supinator.  Origin. — The  lateral  epicondyle  and  upper 
end  of  the  shaft  of  the  ulna.  It  winds  around  the  head  and  neck 
of  the  radius  to  the  insertion  on  upper  part  of  the  shaft.  This  is 
the  chief  supinator;  it  is  entirely  covered  by  other  muscles. 

Action. — It  rotates  the  radius  and  turns  the  dorsum  of  the  hand 
downward  or  backward. 

Nerve. — Deep  branch  of  radial. 

The  brachio-radialis  (Fig.  82).  Origin. — The  lateral  border 
of  the  humerus.     Insertion. — The  styloid  process  of  the  radius. 

Action. — It  assists  in  both  flexion  and  supination  of  the  forearm. 
(This  muscle  was  formerly  called  the  long  supinator.) 

Nerve. — Radial. 

Annular  Ligaments. 

These  are  special  bands  of  deep  fascia  h(jld!ng  in  place  those 
tendons  which  pass  the  wrist-joint.     They  include  the  tendons  in 


I02  '  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

canals  through  which  they  glide  freely.  Friction  is  prevented  by 
synovial  sheaths  within  the  canals.  The  fascia  which  binds  down 
the  extensor  tendons  is  the  dorsal  ligament  of  the  wrist;  that  which 
conlmes  ih.e  Jiexor  tendons  is  the  transverse  ligament  of  the  wrist. 

Muscles  of  the  Palm  (Fig.  82). 

There  is  a  group  of  muscles  in  the  palm  of  the  hand  which 
move  the  thumb  in  various  directions  (flexion,  abduction,  adduction, 
and  so  on).  They  form  the  elevation  called  the  thenar  eminence,  or 
the  "ball  of  the  thumb."  A  similar  group  for  the  little  finger  forms 
the  hypothenar  eminence. 

They  arise  mostly  on  carpal  bones  and  deep  fascia  and  are  inserted  on  first 
phalanges.  In  the  hollow  of  the  hand  between  these  two  eminences  lie  the  long 
tendons,  already  described,  on  their  way  to  the  fingers;  also  some  small  muscles 
between  them  and  beneath  them. 

The  interosseous  muscles  fill  the  interosseous  spaces.  The  action  of  the 
dorsal  group  is  to  spread  the  fingers  apart  (abduction)  while  that  of  the  palmar 
group  is  to  bring  them  together  {adduction) . 

Note. — A  line  drawn  from  the  middle  of  the  wrist  to  the  tip  of  the  middle 
finger  is  called  the  median  line  of  the  hand.  To  abduct  the  fingers  and  thumb  is 
to  draw  them  away  from  this  line,^n  other  words,  from  the  middle  finger.  To 
adduct  them  is  to  draw  them  toward  the  middle  finger. 

Nerves. — To  the  hypothenar  muscles. — Ulnar-  To  thenar  muscles.- — Median 
and  ulnar. 

The  muscles  in  the  palm  are  covered  by  particularly  dense, 
deep  fascia  called  the  pahnar  fascia,  or  palmar  aponeurosis. 

MUSCLES  OF  THE  LOWER  EXTREMITY. 
The  Pelvis — Interior. 

False  pelvis. — The  iliacus  is  the  only  muscle  in  the  false  pelvis; 
it  is  already  described  with  the  psoas  major,  page  93. 

True  pelvis. — The  piriformis.  Origin. — The  front  of  the 
sacrum;  it  passes  out  through  the  great  sciatic  notch  to  the  inser- 
tion on  the  top  of  the  great  trochanter. 

Action. — External  rotation  of  the  femur. 

Nerve. — From  sacral  plexus. 

Obturator  internus  (also  within  the  true  pelvis,  Fig.  87). 

Origin. — The  surface  of  obturator  membrane,  and  a  portion 


MUSCLES    OF    THE    PELVIC    FLOOR. 


103 


of  bone  around  it;  it  passes  out  through  the  small  sciatic  notch 
to  the  insertion  on  the  great  trochanter. 

Action. — External  rotation  of  the  femur. 

Nerve. — From  sacral  plexus. 

The  floor  of  the  pelvis  consists  of  two  flat  muscles  on  either  side, 
the  levator  ani  and  the  coccygeus. 

Their  origin  is  on  the  interior  of  the  pelvic  wall, — that  is,  on 
the  pubic  bone  and  the  spine  of  the  ischium,  and  a  line  of  fascia 


Sacrum 


piriformis 


Coccyx 

Levator  ani  (di- 
vided below 
the  "white 
line") 

Space  for  obtu- 
rator internus 

Rectum 

Prostate 


Symphysis 
Fig. 


Passage  for  glu- 
teal vessels 
and  nerve 

Piriformis 

Passage  for  sci- 
atic and  pu- 
dic  vessels 
and  nerve 

Ischial  spine 

Coccygeus 
Cellular  interval 
Levator  ani 


Capsule  of  pros- 
tate, and  pu- 
bo-  prostatic 
ligaments 


— Interior  and  Floor  of  the  True  Pelvis. — (Morris.) 


between  these  two  points.  Insertion. — The  muscles  meet  each 
other  in  the  median  line,  being  also  attached  to  certain  pelvic 
organs  (bladder  and  rectum  in  the  male;  bladder,  rectum,  and 
vagina  in  the  female)  and  to  the  coccyx.  Their  action  supports 
the  pelvic  organs,  especially  the  rectum,  and  lifts  them  in  various 
motions  of  the  body,  as  in  respiration. 

Xerve. — From  sacral  nerves. 

Special  notes. — These  two  muscles  form  a  concave  floor  like  an  inverted 
dome,  which  is  the  pelvic  diaphragm.     When  this  dome  contracts  it  rises. 

There  are  two  openings  in  the  pelvic  iioor  for  the  bladder  and  rectum,  and  a 
third  opening  in  the  female  pelvis  for  the  vagina. 

The  pelvic  fascia  is  a  continuation  of  the  transversalis  fascia 
which  lines  the  abdomen  and  of  the  iliac  fascia  which  covers  the 


I04 


ANATOMY  AND   PHYSIOLOGY    FOR   NURSES. 


iliacus  muscle.     It  covers  the  obturator  muscle  and  its  fascia  and 
the  muscles  of  the  floor,  and  forms  ligaments  for  the  pelvic  viscera. 


The  Pelvis — Exterior. 

Three  gluteal  muscles. — From  the  three  gluteal  lines  of  the  os 
coxas  and  the  spaces  above  them,  arise  three  gluteal  muscles. 

Gluteus  minimus.  Origin. — The  in- 
ferior line  and  space  above  it.  Insertion. 
— The  front  of  great  trochanter. 

Action. — It  abducts  the  thigh  and  ro- 
tates the  femur  slightly  inward  (so  that 
the  foot  turns  in). 

Gluteus  medius.  Origin. — The  ante- 
iior  or  middle  line  and  space  above  it  up 
lo  the  crest.  Insertion. — The  outer  sur- 
I  ice  of  great  trochanter. 

Action. — Abduction  of  the  femur  and 
-ome  rotation  outward. 

Nerve  of  both. — Superior  gluteal. 

Gluteus  maximus.      Origin. — 

The  posterior  line  and  space  behind 
It  to  the  crest  (also  from  the  back  of 
^dcrum).  Insertion. — The  back  of 
great  trochanter  and  the  shaft  below 
it,  also  the  deep  fascia,  or  fascia  lata. 
Action. — External  rotation  of 
femur;  it  is  also  a  powerful  extensor 
of  the  hip-joint  when  one  rises  from 
the  sitting  position,  or  in  mounting 
steps. 

Nerve. — Inferior  gluteal. 


Fig.  85. — The  Gluteal  Region. 
I,  2,  3,  4,  5,  5,  Gluteus  maximus; 
6,  7,8,  10,  fascia  lata;  9,  lower  end  of 
tensor  fasciae  latae;  11,  upper  portion 
of  biceps  femoris;  12,  upper  portion 
of  semitendinosus;  13,  upper  portion 
of  semimembranosus;  14,  gracilis. 
— (Gould's  Dictionary.) 


It  also  abducts  the  thigh. 


Obturator  extemus.      Origin. — The 

obturator    membrane    and    bone   around 
it.     Insertion. — The  fossa  of  great  trochanter.     Action. — External  rotation 
of   femur.     (Fig.  78.) 
Nerve. — Obturator. 


Practical  point. — Observe  the  number  of  muscles  for  external 
rotation  and  note  that  the  usual  position  of  the  foot  is  with  the  toes 
turned  out. 


THE    QUADRICEPS    FEMORIS, 


105 


Muscles  of  tee  Thigh.  . 
Anterior. 

On  the  front  and  the  sides  of  the  femur  are  the  muscles  which 
extend  the  leg — four  in  number — which  blend  at  their  insertion, 
therefore  constituting  a  four- headed  mus- 
cle, the  quadriceps  femoris.  They  are  the 
rectus  femoris,  the  vastus  lateralis,  vastus 
medialis  and  the  vastus  intermedius. 

Rectus  femoris.  Origin. — The  an- 
terior inferior  spine  of  the  ilium,  and  the 
upper  border  of  the  acetabulum.  The 
three  vasti.  Origin. — On  the  linea 
aspera  and  the  three  surfaces  of  the 
femur.  Insertion  of  the  four. — By  one 
tendon  passing  in  front  of  the  knee-joint 
to  the  tubercle  of  the  tibia.  (It  encloses 
the  patella  and  has  been  improperly 
called  the  ligamentum  patellae.) 

Action. — They  extend  the  leg  as  in 
walking,  or  with  great  force  in  kicking; 
these  muscles  also  keep  the  patella  in 
place  during  various  positions  of  the  knee. 

Nerve. — Femoral. 

The  sartorius. — The  longest  muscle 
in  the  body;  it  passes  across  the  front  of 
the  quadriceps.  Origin. — The  anterior 
superior  spine  of  the  ilium.  Insertion. — 
The  inner  surface  of  the  tibia,  just  below 
the  head. 

Action. — Since  it  passes  across  to  the 
medial  side  of  the  thigh,  and  behind 
the  medial  epicondyle,  it  flexes  the  leg 
and  at  the  same  time  lifts  it  in  such  a 
way  that  when  both  legs  are  acted  upon 
together,  they  Sive flexed  and  crossed,  hence 
the  name,  signifying  "tailor"  muscle. 

Nerve. — Femoral. 

The  tensor  fasciae  latae. — Is  attached  to  the  anterior  part  of  the  crest  of 
the  ilium  between  two  layers  of  the  fascia  lata;  it  makes  tense  the  outer  portion 


Fig.  86. — Muscles  of  the 
Thigh. 
I,  2,  Iliacus  and  psoas;  3, 
4,  tensor  fasciie  latiE;  5,  sar- 
torius; 6,  rectus  femoris;  7, 
vastus  lateralis;  8,  vastus  me- 
dialis; 9,  gracilis;  10,  adduc- 
tor longus;  II,  pectineus. — 
(Holden.) 


io6 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


of  the  fascia  which  is  connected  with  the  tibia,  or  the  ilio-tibial  hand.     (This  is  felt 

like  a  strong  cord  above  the  lateral  epicon- 
dyles.)  It  also  rotates  the  thigh  inward 
(Fig.  86). 

Nerve. — Superior  gluteal. 

Muscles  of  the  Thigh. 
Posterior. 

The  muscles  are  three  in  num- 
ber— the  biceps  femoris,  semiten- 
dinosus,  and  semimembranosus 
(Figs.  87,  d>d>). 

The  biceps  femoris.  Origin. 
— Long  head  on  the  tuber  of  the 
ischium,  short  head  the  linea  aspera 
(lateral  Hp).  Insertion. — ^The 
head  of  the  fibula. 

The  semitendinosus  and  the 
semimembranosus  also  arise  on 
the  tuber  of  the  ischium,  and  are 
inserted  on  the  tibia,  medial  surf  ace 
and  back  of  head.  (Their  names 
indicate  their  shape,  one  being 
tendinous  in  half  its  length,  and 
the  other  aponeurotic,  or  mem- 
branous.) 

Action. — These   three  muscles 
act  together  to  flex  the  knee. 
Nerve  to  the  three. — Sciatic. 


LE.E   Lu^  J., 

Fig.  87. — Medial  Aspect  of  the 
Thigh  and  Pelvis. 
I,  2,  3,  4,  Iliacus,  psoas,  obturator, 
piriformis;  5,  gluteus  maximus;  6, 
sartorius;  7,  gracilis;  8,  semitendinosus; 
9,  semimembraDosus  10,  11,  12,  ten- 
dons of  sartorias,  gracilis,  and  semi- 
tendinosus; 14,  tendon  of  semimem- 
branosus.— (Gould's  Dictionary.) 


Notes. — They  also  assist  the 
gluteus  maximus  to  extend  the  thigh, 
as  in  rising  from  a  chair.  The 
biceps  tendon  may  be  felt  behind 
the  lateral  epicondyle;  the  two 
others,  behind  the  medial  epicondyle,  making  the  borders  of  a 
deep  space — the  popliteal  space,  or  ham.  They  are  called  "ham- 
string" tendons. 


MUSCLES    OF    THE    LOWER   EXTREMITY. 


107 


Fascial  insertion  of 
gluteus  maximus 


Biceps 


Vastus  lateralis 


Plan  tans 


Gastrocnemius 


Solcus 


Peroneus  longus 


S  emi-membranosus 


Semi-tendinosus 


G  racilis 

Tendon  of  semi-membranosus 


—  Sartorius 


I'lexor  digitorum  longus 


Tcndo  Achillis 


Fig.  88.— Posterior  of  Thigh  and  Leg  and  Hamstring  Tendons  (Morris). 


io8 


ANATOMY  AND   PHYSIOLOGY    FOR   NURSES. 


Hamstring    tendons. 


I  Lateral  side,  biceps  femoris. 
semitendinosus. 
Medial  side,   ,    semimembranosus, 
sartorius. 
gracilis. 

The  popliteus  is  a  flat  muscle  behind  the  knee-joint,  forming  part  of  the 
floor  of  the  popliteal  space. 

The  most  important  muscles  in  the  medial  side  of  the  thigh 
are  the  four  adductors  (Fig.  89). 

The  adductor  longus.  Origin. — From  the 
superior  ramus  of  the  pubes.  Insertion. — The 
middle  of  the  linea  aspera. 

The  adductor  brevis.  Origin. — Upper  part  of 
the  pubic  arch.  Insertion. — The  linea  aspera 
behind  and  above  the  longus. 

The  adductor  minimus.  Origin. — The  lower 
part  of  the  pubic  arch.  Insertion. — The  linea 
aspera,  behind  the  brevis  (upper  part). 

The  adductor  magnus.  Origin. — Pubic  arch 
and  tuber  of  the  ischium.  Insertion. — Linea 
aspera  (behind  the  others),  and  medial  epicondyle. 

Action  of  the  four. — They  all  adduct  the 
femur  (rotating  it  outward)  and  draw  the 
thighs  together  as  in  horseback  riding. 

Nerve  to  the  four.-^^Obturator. 

Note. — The  magnus  makes  a  broad  sheet  of 
muscle  between  the  quadriceps  which  extends  the 
knee,  and  the  muscles  on  the  back  which  flex  it.  The 
longest  and  strongest  fibers  of  the  magnus  rotate  the 
femur  inward.  They  run  between  the  tuber  of  the 
ischium  and  the  medial  epicondyle. 

Muscles  of  the  Leg. 
Anterior. 
These  muscles  flex  the  ankle  and  extend 
the  toes.^ 

The  muscles  in  the  front  of  the  leg  are 

between  the  tibia  and  the  fibula;  the  medial 

surface  of  the  tibia,  having  no  muscles  upon  it,  is  called  subcutaneous. 

The  tibialis  anterior.     Origin. — The  shaft  and  head  of  the 

tibia  (lateral  surface)  and  the  interosseous  membrane. 

'  Note. — This  movement  of  the  toes  is  dorsal  flexion. 


Fig.  89. — Adductors. 
I,  2,  3,  Femur,  ilium, 
pubes;  4,  external  obtura- 
tor muscle;  5,  6,  7,  8,  9, 
10,  adductor  muscles;  11, 
12,  openings  for  vessels 
passing  to  back  part  of 
thigh. — (Gould's  Diction- 
ary). 


MUSCLES    OF    THE    LEG. 


109 


Insertion. — The  first  cuneiform  and  first 
Nerve. — Deep  peroneal. 

The   peroneus    tertius.     Origin. — The 

(lower  part).  Insertion. — The  fifth  metatar- 
sal bone. 

Action  of  the  two. — To  flex  the  ankle. 
The  tibialis  acting  alone  lifts  the  medial 
border  of  the  foot;  the  peroneus  lifts  the  lateral 
border. 

Nerve. — Deep  peroneal. 

The  extensor  hallucis  longus,  or  long 
extensor  of  the  great  toe.  Origin. — The  shaft 
of  the  fibula  and  the  interosseous  membrane. 
Insertion. — The  last  phalanx  of  the  great  toe. 

Action. — To  extend  the  great  toe. 

Nerve. — Deep  peroneal. 

The  extensor  digitonim  longus,  or  long 
extensor  of  the  toes.  Origin. — The  shaft  of 
the  fibula  and  interosseous  membrane  (a  few 
fibers  from  head  of  tibia).  Insertion. — By- 
four  tendons  on  the  second  and  third  phalanges 
of  the  four  lateral  toes,  like  the  similar  extensor 
of  the  fingers. 

Action. — To  extend  the  toes. 

Nerve. — Deep  peroneal. 

Note. — These  two  muscles,  since  they  pass 
in  front  of  the  ankle- joint,  flex  it. 

On  the  dorsum  of  the  foot  the  extensor  digitorum 
brevis  has  four  slender  tendons  for  the /oMrwze^fza/ toes. 
Nerve. — Deep  peroneal. 

Muscles  of  the  Leg. 
Posterior. 


metatarsal  bones, 
shaft    of    the    fibula 


Fig.  90. — Muscles  of 
THE  Leg,  Anterior. 
I,  Rectus  femoris; 
2,  tibia;  3,  tibialis  an- 
terior; 4,  long  extensor 
of  toes;  5,  long  extensor 
of  great  toe;  6,  peroneus 
tertius;  7,  8,  peroneus 
longus,  p.  brevis;  9,  10, 
lateral  and  medial  heads, 
gastrocnemius;  11,  short 
extensor  of  toes;  12,  an- 
nular ligament  (Gould's 
Dictionary) 


These  muscles  extend  the  ankle  and  flex  the  toes;  they  all  pass 
behind  the  medial  malleolus.     They  are  covered  by  the  calf  muscles. 

The  tibialis  posterior.     Origin. — Shaft  of  both  tibia  and  fibula  and  the 
interosseous  membrane.     Insertion. — Navicular  and  first  cuneiform  bones. 
Action. — Extension  of  the  ankle. 
Nerve. — Tibial. 


no 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


The  long  flexor  of  the  great  toe,  or  flexor  hallucis  longus.     Origin. — Shaft 
of  fibula.     Insertion. — Last  phalanx  of  the  great  toe  (Fig.  91). 
Nerve. — Tibial. 

Long  flexor  of  the  toes,  or  flexor  digitorum  longus.  Origin. — Shaft  of 
fibula.  Insertion. — By  four  tendons  on  the  last 
phalanges  of  the  four  lateral  toes  (Fig.  91). 

Action  of  these  two  muscles. — Flexion  of  the  tips  of 
the  toes. 

Nerve. — Tibial. 

Leg — Lateral  Side  (Fig.  92). 

Peroneus  longus.  Origin. — Shaft  of  fibula. 
Insertion. — In  the  sole  of  the  foot,  first  meta- 
tarsal bone.  The  tendon  passes  behind  the  lateral 
malleolus  and  crosses  in  the  sole  to  the  medial 
border  of  the  foot. 

Peroneus  brevis.  Origin. — Shaft  of  fibula. 
Insertion. — Base  of  fifth  metatarsal  bone.  The 
tendon  passes  behind  the  lateral  malleolus. 

Action  of  these  two  muscles. — They  extend 
the  ankle  and  lift  the  lateral  border  of  the  foot. 

Nerve  to  both. — Superficial  peroneal. 

Note. — As  the  tibialis  anterior  and  peroneus 
tertius  flex  the  foot,  so  the  tibialis  posterior  and 
peroneus  brevis  extend  it. 

Orthopedic  note. — The  P.  longus  makes  a 
chord  for  the  transverse  arch  of  the  foot,  being 
the  most  important  muscle  to  preserve  that  arch 
from  being  flattened. 


Fig.  91 . — Mus- 
cles OF  THE  Plan- 
tar Region,  Mid- 
dle Layer. 

I,  Accessory  mus- 
cle; 2,  long  flexor  of 
toes  dividing  into  four 
tendons;  3,  tendon  of 
long  flexor  of  great 
toe;  4,  5,  6,  7,  8, 
plantar  muscles;  9, 
projection  of  fifth 
metatarsal  bone;  10, 
sheath  of  tendon  of 
peroneus  longus;  11, 
calcaneus  (Gould's 
Dictionary) . 


Calf  Muscles  (Figs.  8S,  92). 
Triceps  surae,  and  plantaris. 

The  gastrocnemius.  Origin. — By  two  heads  just  above  the 
condyles  of  the  femur.     Insertion. — On  the  calcaneus. 

Note. — The  two  heads  form  the  lower  boundaries  of  the  popliteal 
space. 

The  soleus  is  covered  by  the  gastrocnemius.  Origin. — Medial 
border  of  the  tibia  and  lateral  border  of  the  fibula.  Insertion. — 
The  OS  calcis,  with  the  above  muscle. 

Action  of  the  two. — They  join  to  form  one  muscle,  the  triceps 


TRICEPS    SUR^    (calf    MUSCLES). 


Ill 


surae  (or  triceps  of  the  ealf),  which  has  the  strongest  tendon  in  the 
body,  the  tendo  calcaneus  {tendon  of  Achilles)  by  which  they  are 
attached  to  the  os  calcis,  and,  therefore,  they  lift  the  heel.  If  the 
muscles  of  both  legs  act  at  the  same 
time,  the  whole  body  is  lifted  on  the 
toes. 

Nerve  to  both. — Tibial. 

The  plantaris.  Origin. — With  the  outer 
head  of  the  gastrocnemius.  Insertion. — 
With  the  tendo  calcaneus. 

Note. — The  belly  is  short  and  small;  the 
tendon  is  the  longest  in  the  body. 

The  calf  muscles  constitute  a 
group  of  great  power,  as  by  them  one 
lifts  oneself  to  stand  upon  the  toes. 

The  sole  of  the  foot,  or  plantar 
region,  resembles  the  palm  of  the 
hand  in  having  special  groups  of  mus- 
cles for  the  great  and  little  toes,  with 
the  long  flexor  tendons  lying  between 
them,  and  a  dense  fascia  covering 
them.  This  is  called  the  plantar 
fascia. 

The  nerves  are  medial  and  lateral  plantar. 

Annular  Ligaments. 

The  tendons  which  pass  from  the 
leg  to  the  foot  are  kept  in  place  by 
special  ligaments,  anterior  and  lateral, 
and  surrounded  by  synovial  sheaths 
as  in  the  wrists. 


Fig.  92. — Lateral  Aspect  and 
Calf  of  Leg. 
I,  2,  3,  4,  Lateral  view,  muscles 
passing  in  front  of  ankle;  5,  6, 
peroneus  brevis  and  p.  longus  (be- 
hind ankle) ;  7,  8,  soleus  and  gas- 
trocnemius; 9,  head  of  fibula;  10, 
biceps  femoris;  11,  semimembra- 
nosus; 13,  tendo  Achillis;  15,  an- 
nular ligament;  16,  17,  insertions 
of  peroneus  tertius  and  brevis;  18, 
short  extensor  of  toes;  19,  plantar 
muscle;  20,  patella  (Gould's  Dic- 
tionary) . 


Points. — Eversion  of  the  foot,  or  lifting  the  medial  border,  is  done  by  the 
tibialis  anterior. 

Inversion. — Or  lifting  the  lateral  border,  by  the  peroneus  tertius,  and  pero- 
neus longus. 

Adduction.— By  deep  fjostcrior  muscles  of  the  leg. 

Abduction. — By  external  muscles  of  the  leg. 

Observe  certain  similarities  and  differences  in  the  extremities. 
Extension  of  the  elbow  is  accomplished  by  the  three-headed  muscle, 


112  ANATOMY  AND   PHYSIOLOGY    FOR    NURSES. 

the  triceps.  Extension  of  the  knee  requires  a  powerful  four-headed 
muscle,  the  quadriceps. 

The  great  toe  is  on  the  medial  border  of  the  foot,  the  thumb  is  on 
the  lateral  border  of  the  hand.  This  is  so  because  the  terms  medial 
and  lateral  are  applied  to  the  pronated  position  of  the  lower  extremity 
and  the  supinated  position  of  the  upper  extremity. 

In  the  upper  extremity  the  joints  are  all  flexed  in  one  direction,  as 
though  the  limb  might  be  rolled  up.  In  the  lower  extremity  they 
flex  and  extend  alternately,  as  though  the  limb  were  folded  back 
and  forth. 

STRUCTURE  AND  PHYSIOLOGY  OF  MUSCLES. 

A  completed  muscle  is  a  complicated  structure.     It  consists  of: 

First,  the  essential  muscle  substance  in  the  muscle  cells. 

Second,  connective  tissue  wrappings  and  partitions. 

Third,  tendons  and  aponeuroses. 

Fourth,  blood  and  lymph  vessels. 

Fifth,  muscle  nerves. 

The  connective  tissue  supports  all  of  the  other  structures  and 
protects  the  muscle,  preserving  its  shape  and  stability. 

The  tendons  and  aponeuroses  provide  a  means  whereby  the  attach- 
ment to  other  organs  is  kept  within  a  small  space. 

Example:  The  biceps  of  the  arm  contains  many  fibers,  but  the  slender  ten- 
dons of  this  muscle  occupy  only  small  areas  upon  the  surface  of  the  bones. 
The  aponeurosis  of  that  very  powerful  muscle,  the  quadriceps  femoris,  re- 
ceives the  insertion  of  the  muscle  fibers,  and  by  this  means  only  a  narrow 
surface  is  required  for  insertion  upon  the  bone.  But  for  arrangements  like 
these,  the  skeleton  would  of  necessity  be  inconveniently  large. 

The  blood-vessels  bring  the  nutritive  fluid  which,  in  the  tissue- 
spaces,  bathes  each  little  fiber,  and  is  gathered  up  by  the  lymph 
vessels. 

The  nerves  bring  to  each  fiber  its  natural  stimulus  to  action. 

The  work  of  muscle  tissue  is  done  in  the  fiber  cell.  This 
when  stimulated,  contracts,  bringing  the  two  ends  of  the  fiber 
nearer  to  each  other,  and  naturally  the  fiber  swells  as  it  shortens. 
So  with  the  myriad  of  fibers  in  a  muscle;  when  they  contract,  the 
muscle  swells  and  shortens  (Fig.  93  illustrates  the  changes  pro- 
duced). This  results  in  motion,  which  appears  as  the  organs 
attached  are  moved.  . . 


PHYSIOLOGY    OF   MUSCLES, 


"3 


All  skeletal  muscles  are  so  attached  as  to  be  tense,  that  is,  they 
are  just  a  little  stretched,  so  that  it  is  easier  for  them  to  act  than 
not.  (A  cut  across  a  muscle  releases  it  from  tension  and  leaves 
a  gaping  wound.) 

The  actions  of  muscles  are  regulated  by  their  attachments,  and 
the  function*  is  often  expressed  in  the  name.  If  muscles  or  their 
tendons  pass  in  front  of  a  joint,  for  instance,  causing  flexion,  they 
are  frequently  csdled  Jlexors ;  or  if  they  pass  behind  such  joints, 
they  may  be  called  extensors;  and  so  with  other  muscles  and 
joints.  Examples:  Flexors  of  the  wrist,  extensors  of  the  fingers, 
etc.  Many  other  examples  will  occur  to  the  student,  as  abductors, 
adductors,  pronators,  etc. 


Fig.  93.— Showing  Change  of  Shape  in  Contraction  (Brubaker). 


As  the  location  determines  the  function  of  a  muscle,  so  it  often 
suggests  the  name,  as  the  pectoralis  major  and  minor,  the  intercostals, 
etc.  Sometimes  the  shape  is  named,  as  the  orbicularis  of  the  mouth 
or  of  the  eyelids  (orbicular  muscles,  or  sphincters,  surround  and  con- 
trol openings).  Shape  and  location  may  together  suggest  a  name 
sometimes,  as  the  latissimus  dorsi,  the  rectus  abdominis  (broadest  of 
the  back  and  straight  of  the  abdomen)^  and  others,  expressing  or 
implying  the  function  of  the  muscle. 

One  of  the  most  useful  and  interesting  muscles  in  the  body  is  the 
diaphragm.  Although  a  voluntary  muscle  in  structure,  it  is  asso- 
ciated with  visceral  action.     (For  general  description  see  page  91.) 

The  special  interest  attending  this  muscle  arises  from  its  location 

'  The  full  Latin  name  includes  the  word  musculus  {muscle) ;  for  the  sake  of  brevity  it 
is  omitted. 
8 


114  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

as  well  as  its  structure.  Situated  between  the  great  cavities  of  the 
trunk  it  acts  upon  the  organs  belonging  to  both.  In  contraction,  it 
encroaches  upon  the  cavity  of  the  abdomen  pressing  upon  abdominal 
organs,  and  thus  aids  in  expelling  the  contents  of  abdominal  and 
pelvic  viscera.  In  this  act  (expulsion  from  abdomen,  or  pelvis)  it  is 
fixed  in  contraction  (holding  the  breath)  so  that  other  muscles  can 
act  efficiently.  Examples:  defecation,  parturition.  Ceasing  to  con- 
tract it  rises  to  its  inactive  or  dome-shape;  and  as  this  is  accompanied 
by  slight  abdominal  pressure  upward,  the  effect  upon  the  thorax  is 
to  shorten  it,  causing  gentle  pressure  upon  the  lungs.     • 

In  contraction,  therefore,  it  compresses  the  abdomen  and  enlarges 
the  thorax;  in  relaxation,  it  enlarges  the  abdomen  and  compresses 
the  thorax.  This  alternate  enlargement  and  compression  of  the 
thorax  explains  its  most  important  function — that  of  a  breathing 
muscle,  or  muscle  of  inspiration. 

Special  points. — The  lateral  portions  of  the  diaphragm  are  the 
most  movable  portions,  being  mostly  muscular.  Here  the  lungs  rest 
upon  the  falling  and  rising  floor,  themselves  alternately  expanding 
and  contracting.  The  heart  lies  upon  the  least  movable  portion 
— consequently  the  diaphragm  supports  the  heart  but  does  not 
press  against  it  unless  pushed  up  from  below. 

Similar  fimctions  pertain  to  another  muscle  constituting  the  floor 
of  the  pelvis  (the  levator  aniandcoccygeus  taken  together),  which  rises 
and  falls  with  the  displacement  and  functionating  of  abdominal 
organs.  With  the  combined  contraction  of  these  two,  and 
relaxation  of  the  diaphragm,  the  whole  body  of  abdominal  and 
pelvic  organs  moves  upward,  and  vice  versa. 

Passing  to  the  consideration  of  more  complicated  movements, 
we  find  that  all  functions  of  the  body  depend  in  the  beginning  upon 
muscle  action. 

For  respiration  we  must  have  the  muscles  of  the  thorax;  for 
swallowing  or  deglutition,  the  muscles  of  the  tongue  and  throat;  for 
speaking,  those  of  the  tongue  and  face:  The  heart  itself  is  a  collection 
of  muscles  influencing  the  entire  body,  since  without  circulation  of 
blood  all  processes  of  life  must  cease. 

The  arms  and  hands  become  organs  of  prehension  when  by  use  of 
their  numerous  muscles  they  reach  out  to  gather  things  in;  the  lower 
limbs  are  organs  of  locomotion,  only  because  their  muscles  enable 
them  to  bear  and  transport  the  body  from  place  to  place.     Even  the 


FUNCTIONS    OF    MUSCLES.  II5 

ability  to  stand  still  is  due  to  a  balanced  tension  of  muscles,  which 
keeps  the  joints  quiet. 

Finally,  various  emotions  may  be  expressed  by  muscle-action 
without  a  spoken  word,  both  by  changes  of  the  face  (referred  to,  p. 
82)  and  gestures  of  the  body.  Compare  the  erect  posture  of  the 
person  ready  and  alert,  with  the  drooping  figure  of  despondency  or 
the  lax  one  of  indolence.  Read  the  meaning  of  the  firm,  quick 
footstep,  and  contrast  it  with  the  uncertain  and  halting  one.  Note 
how  the  hand  may  welcome,  or  repel.  Even  the  eye  would  be  far 
less  expressive  were  the  iris  immovable.  Indeed,  we  might  well  see 
a  literal  meaning  in  the  old  adage — "Actions  speak  louder  than 
words."  Thus  muscle  action  means  much  more  than  simple 
movement,  and  it  all  depends  ultimately  upon  the  specially  developed 
attribute  of  the  muscle  cell — contractility. 

Muscle  Tissue,  a  Source  of  Heat  and  Electricity. 

Thus  far  we  have  considered  only  one  result  of  muscle  action; 
namely,  the  production  of  fnotimi.  Muscle  tissue  is  built  up  of  food 
derived  from  the  blood — contraction  means  a  using  up  of  its  sub- 
stance, and  the  formation  of  waste  products.  These  chemical  pro- 
cesses are  going  on  continually,  and  all  chemical  action  is  accompan- 
ied by  the  production  of  heat.  A  muscle  in  action  is  therefore  a 
machine  for  producing  body  heat,  and  since  the  muscular  system 
comprises  so  large  a  portion  of  the  human  body  (weighing  nearly 
three  times  as  much  as  the  bones),  it  is  one  of  the  chief  sources  of 
heat;  for  the  double  reason  that  it  includes  a  great  deal  of  tissue,  and 
that  it  is  more  constantly  at  work  than  any  other  tissue  in  the  body. 

We  all  know  that  the  body  temperature  rises  during  muscular 
exercise;  as  the  vessels  dilate,  bringing  oxygen  for  chemical  action, 
heat  is  rapidly  evolved  and  v/aste  is  swept  away.  (Blood-  and  lymph 
vessels  carry  both  food  and  waste.) 

In  addition  to  other  results  of  muscle  activity,  a  slight  current  of 
electricity  is  produced,  appreciable  only  by  certain  experiments. 

Modifications  of  Muscle  Action. 

Clinical  notes. — Tetanus  is  a  condition  of  the  muscles  in  which 
the  contractions  are  so  rapid  that  the  action  appears  to  be  continuous; 
the  stimuli  come  so  rapidly  that  the  fibers  cannot  relax. 


ii6 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


It  may  be  due  to  various  causes:  to  drugs,  as  strychnine;  to 
bacterial  poisoning  through  invasion  of  wounds,  or  to  disordered 
conditions  of  the  nerve  system.  It  may  be  voluntary  in  character. 
When  one  deliberately  stiffens  the  body  or  any  portion  of  it  the 
rigidity  thus  occurring  is  tetanic. 

Cramp  is  sudden  involuntary  contraction  of  muscle-fiber, 
spasmodic  in  character  and  so  violent  as  to  be  exceedingly  painful. 

Convulsive  movements  or  convulsions  {spasms)  are  due  to  involun- 
tary and  forcible  action  of  several  muscles  or  groups  of  muscles. 

The  movements  vary  with  the  number  of  muscles  involved. 

Fatigue  of  muscle  tissue  follows  prolonged  use,  evidenced  by 
sensations  of  pain  in  the  muscles  themselves,  probably  due  to  an 
accumulation  of  waste  matters  when  the  muscle  is  not  quite  equal  to 
the  demands  made  upon  it. 

LARGE  MUSCLES  CLASSIFIED  ACCORDING  TO  THEIR  MOST 
FREQUENT  ACTION. 


Region. 

Action. 

Muscles. 

■ 

Trunk 

To  enclose  cavities  and  aid  in 
respiration 

To  separate  cavities  and  aid  in 
respiration 

Intercostals. 
Quadratus  lumborum. 
Obliquus  externus. 
Obliquus  internus. 
Transversus. 

Diaphragm. 

Levator  ani. 

Floor  of  trunk  and  aiding  above 
muscles 

Head     

To  move  spine  and  trunk •. 

Coccygeus. 
Abdominal  group. 
Erector  spinas. 
Ilio-psoas. 
Erector  spinae. 
Trapezius. 
Sterno-mastoids. 

To  flex  head 

Shoulder 

To  rotate  head . 

To  lift  shoulder 

Trapezius. 

Sterno-mastoid. 

Trapezius. 

Trapezius. 

Anterior  serratus. 

Pectorals. 

Arm 

To  pull  shoulder  backward 

To  pull  shoulder  forward 

To  pull  arm  forward.         .... 

To  pull  arm  backward 

Latissimus  dorsi. 

To  abduct  (lift)  arm 

To  adduct  (pull  downward) 

To  rotate  arm  {supination) 

To  rotate  arm  {pronation) 

Deltoid. 
Pectorals. 
Latissimus  dorsi. 
Infraspinatus. 
Teres  minor. 
Subscapularis. 
Teres  major. 

FUNCTIONAL    CLASSIFICATION   OF    MUSCLES. 


117 


LARGE  MUSCLES  CLASSIFIED  ACCORDING  TO  THEIR  MOST 
FREQUENT  ACTION.— (Continued.) 


Region. 


Action. 


Muscles. 


Forearm . 


Wrist. 


Hand. 


Thigh. 


Leg. 


Ankle  . 


Foot. 


To  flex  forearm 

To  extend  forearm 

To  rotate  {supination) 

To  rotate  {pronation) 

To  flex  wrist 

To  extend  wrist 

To  flex  fingers 

To  extend  fingers 

To  flex  thumb 

To  extend  thumb 

To  flex  thigh 

To  extend  thigh 

(also  to  extend  trunk) 

To  rotate  (outward) 


To  rotate  (inward) . 


To  abduct 

To  adduct 

To  flex  leg 

To  extend  leg 

Rotation  (outward) 
Rotation  (inward) . 
To  flex  ankle 

To  extend  ankle. . . 

To  flex  toes 

To  extend  toes 


Biceps  brachil. 

Brachialis. 

Brachio-radialis. 

Triceps. 

Supinator. 

Biceps  brachii. 

Brachio  radialis. 

Pronator  teres. 

Pronator  quadratus. 

Flexor  carpi  radialis. 

Flexor  carpi  ulnaris. 

Extensor     carpi     radialis, 
(long  and  short). 

Extensor  carpi  ulnaris. 

Flexor  digitorum  (sublim.). 

Flexor    digitorum    (pro- 
fund.). 

Extensor  digitorum  (com.). 

Thenar  group. 

Three  extensors  of  thumb. 

Ilio-psoas. 

Gluteus  Maximus. 

Biceps  femoris. 

Semitendinosus. 

Semimembranosus. 

Glutei-med.  and  min. 

Sartorius. 

Four  adductors. 

Two  obturators. 

Gluteus  min. 

Tensor  fasciae  latse. 

Adductor     magnus     (long 
fibers  of) . 

Three  glutei. 

Four  adductors. 

Biceps  femoris. 

Semitendinosus. 

Semimembranosus. 

Sartorius. 

Quadriceps  femoris,  (rectus 
and  three  Vasti.) 

Sartorius. 

Biceps. 

Tibialis  ant. 

Peroneus  tertius. 

Tibialis  post. 

Peronei  (long  and  short). 

Flexor  digitorum  (longus). 

Flexor  pollicis  (longus). 

Extensor    digitorum 
(longus). 

Extensor  hallucis  (longus). 


Il8  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

SPINAL  NERVE  SUPPLY  TO  PRINCIPAL  MUSCLE  GROUPS. 


Region. 


Muscles. 


Nerve. 


Side  of  Neck. 


Thorax  and  Shoul- 
der  


Arm,  anterior. 


Arm,  posterior 

Forearm,  posterior. 

Forearm,  anterior.  . 


Hand. 


Abdomen  and  Pelvis  . 


Thigh 

Thigh,  anterior. 


Thigh,  posterior.  . . 


Three  scaleni  muscles. 
Elevator  of  angle  of  scapula .... 

Intercostal 

Diaphragm 

Sacro-spinalis  (erector  spinae) ... 

Latissimus  dorsi 

Supra-  and  infraspinatus 

Subscapularis . 

Teres  major , 

Teres  minor , 

Deltoid 

Pectoralis  major  and  minor , 

Biceps. 

Coraco-brachialis , 

Brachialis , 

Triceps. 

Supinators  and  extensors  of  wrist 

Extensors  of  fingers 

Pronators  and  superficial  flexors. 
Flexor    carpi    ulnaris    and    deep 

flexors , 

(The  deep  flexor  of  fingers  has 

also  a  branch  from  median.) 
Thenar    eminence    (muscles    of 

thumb) 

Hypothenar    eminence    (muscles 

of  little  finger) , 

Interossei 

Rectus  and  pyramidalis. 
Quadratus  lumborum. 
External  and  internal  oblique . 
Transversus . 

Psoas  and  iliacus 

Levator  ani. 

Perineal  muscles 

Piriformis 

Gluteus  maximus 

Gluteus  medius  and  minimus. 

Tensor  f asciee  latae 

Obturator,  external  and  internal. 
Three  adductors. 

Gracilis 

Quadriceps. 

rectus, 
two  vasti. 

crureus 

Biceps. 

Semitendinosus . 
Semimembranosus 


Cervical  branches  of  bra- 
chial plexus. 

Intercostal. 

Intercostal  and  phrenic. 

Spinal. 

Long  subscapular. 

Suprascapular. 

Subscapular.  _         \ 

Axillary,  (f c  \  R-<i-  "^  ^■     U  ^  /  J 
Axillary  and  ant.  thoracic. 
Ant.  thoracic. 

Musculo-cutaneous. 
Musculo-cutaneous  and 
radial. 

Radial  (musculo-spiral) . 
Deep  branch  of  radial. 
Median. 

Uhiar. 


Ulnar  and  median. 


Ulnar. 
Ulnar. 


Lumbar  plexus. 

Pudic. 

Sacral  plexus. 
Inferior  gluteal. 

Superior  gluteal. 
Obturator. 

Femoral  (anterior  crural). 
Sciatic. 


NERVES    TO    MUSCLES   AND    JOINTS.  II9 

SPINAL  NERVE  SUPPLY  TO  PRINCIPAL  MUSCLE  GROL'FS— (Continued.) 


Region. 


Muscles. 


Nerve. 


Leg,  anterior Anterior  muscles  (extensors) Deep     peroneal     (anterior 

tibial) . 


Leg,  lateral. 


Peroneus  longus  and  brevis. 


Leg,  posterior ]  Calf  muscles. 

Deep  muscles  (flexors) 
Foot 


Superficial  peroneal  (mus- 
culo-cutaneous) . 

Tibial  nerve. 


'  Dorsum Deep  and  superficial  pero- 

I    neal. 
Plantar  region Medial  and  lateral  plantar. 


CHAPTER  VIIL 
THE  ORGANS  OF  DIGESTION. 

MOUTH,   PHARYNX,    ESOPHAGUS,    STOMACH,   AND 

INTESTINES. 

These,  with  the  glands  which  secrete  the  digestive  fluids,  con- 
stitute the  digestive  apparatus. 


y^ 


•Jff ASalivary  Glatui 


Fig.  94. — General  Scheme  of  the  Digestive  Tract,  with  the  Chief  Glands 
Opening  into  It;  together  with  the  Lacteals  Arising  from  the  Intestine 
AND  Joining  the  Thoracic  Duct  (Landois). 

The  alimentary  tract  or  canal  is  a  series  of  channels  included 
within  the  organs  named,  constituting  a  long  tube  of  mucous  mem- 

120 


THE    MOUTH.  121 

brane  through  which  the  food  passes.  The  glands  which  secrete 
the  digestive  fluids  open  into  this  tract. 

The  digestive  fluid  of  the  mouth  is  saliva. 

The  digestive  fluid  of  the  stomach  is  gastric  juice. 

The  digestive  fluids  of  the  intestines  are  intestinal  juice,  and 
pancreatic  juice  (assisted  by  hile). 

Each  of  these  fluids  contains  one  or  more  of  the  peculiar  sub- 
stances called  enzymes. 

An  enzyme  is  a  ferment  which  by  its  presence  causes  certain 
changes  in  other  substances. 

The  enzymes  of  the  digestive  fluids  cause  the  chemical  changes  in 
food  which  are  necessary  for  its  digestion. 

I   Salivary,  opening  into  the  mouth. 

I   Peptic,  "  "     stomach. 

The  glands  are        ]   Intestinal,    "  "     intestines. 

Pancreas,     "  "     small  intestine. 

.  Liver,  "  "     small  intestine. 

The  tongue,  teeth  and  glands  are  appendages  of  the  alimentary  canal. 

The  Mouth. 

The  mouth,  or  oral  cavity,  is  enclosed  partly  by  muscles  and 
partly  by  bones.  The  muscles  are  the  lip  muscles  in  front,  the  bucci- 
nator at  the  sides,  and  the  mylo-hyoid  in  the  floor.  The  bones  are 
the  maxilla  and  the  palate-hones  above,  and  the  mandible  below.  - 

The  roof  of  the  mouth  is  called  the  palate ;  the  bony  portion  is 
the  hard  palate,  and  the  muscular  portion  attached  to  it  is  the  soft 
palate  or  the  velum  palati  (veil  of  the  palate).  In  the  middle  of  the 
soft  palate  is  the  uvula,  which  is  a  small  projection  downward. 
All  of  these  bones  and  muscles  are  in  pairs,  right  and  left. 

Surgical  note. — If,  owing  to  lack  of  development  they  are  not  joined  in  the 
middle  line,  cleft  palate  results.  The  cleft  may  be  partial  or  complete,  and  the 
divided  upper  lip  is  called  harelip. 

The  oral  cavity  is  lined  with  mucous  membrane  which  is  always 
moist  in  health.  The  part  of  the  cavity  between  the  lips  and  the 
teeth  is  the  vestibule. 

The  mouth  contains  the  teeth  and  the  tongue. 

The  teeth  are  already  described. 

The  tongue  lies  in  the  floor  of  the  mouth  with  its  base  curved 
downward  at  the  back  and  attached  to  the  hyoid  bone.     It  is  com- 


122 


ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 


posed  of  muscles,  and  covered  with  mucous  membrane  which  forms 
a  special  fold  underneath  the  tip  of  the  tongue  connecting  it  with  the 
floor;  this  fold  is  called  the  frenum  lingua.  When  the  frenum  is 
short  we  say  the  tongue  is  "tied." 

A  little  clip  with  the  scissors  is  often  sufficient  to  free  it,  but  this  is  done  with 
care  as  an  artery  runs  forward  very  near  the  frenum. 


Septum 
Nostril 


Anterior  naris 


Hard  palate 


Anterior  palatine  , 

arch 

Recess 
Posterior  palatine 

arch 


Tongue 


Fig.  95. — The  Oral  Cavity  (Deaver). 

The  dorsum,  or  superior  surface  of  the  tongue,  is  covered  with 
small  projections  called  papillcs,  of  three  sizes, — the  vallate,  the 
largest,  forming  a  V-shaped  row  at  the  back;  the  fungiform,  next  in 
size,  scattered  over  the  surface  but  most  numerous  at  the  tip  and 
sides,  and  bright  red  in  color;  and  the  filiform,  the  smallest,  covering 
the  anterior  two-thirds  of  the  dorsum  and  borders  (Fig.  96). 

The  tongue  aids  in  mastication  and  swallowing,  or  deglutition.  It 
is  also  an  important  organ  of  speech  and  the  principal  organ  of  taste. 


THE    PALATINE   ARCHES. 


123 


Note. — The  perception  of  bitter  substances  is  plainer  in  the  posterior  portion, 
while  cweet,  sour,  and  salty  substances  are  more  quickly  recognized  in  the 
anterior  part  and  at  the  borders. 

Some  elevations  of  mucous  membrane  on  either  side  of  the  base  of  the 
tongue  form  the  lingual  tonsils.  (These  are  seen  only  with  the  aid  of  the 
laryngoscope.) 

The  mouth  opens  at  the  back  into  the  pharynx,  through  the  pas- 
sage called  the  isthmus  of  the  fauces.  This  passage  is  bounded  by 
two  folds  on  each  side  running  downward  from  the  soft  palate  and 


Parotid 

gland 


Masseter 
muscle 


Hyoid  bone 


Submaxillary  gland 

(main  portion  is  drawn  backward) 

Fig.  96. — Salivary  Glands  and  Papilla  of  Tongue  (Morris). 

called  the  palatine  arches,  or  pillars  of  the  fauces.  Between  the  an- 
terior and  posterior  arch  of  either  side  is  the  palatine  tonsil,  a  gland- 
like body  the  use  of  which  is  not  clearly  understood^  (Fig.  95). 

It  presents  small  openings  upon  its  surface  leading  into  recesses  or  crypts 
which  are  surrounded  by  the  follicles  of  the  tonsils. 

Clinical  note. — Follicular  tonsillitis  is  an  inflammation  of  the  mucous 
membrane  and  follicles  in  the  crypts. 

'  The  student  may  see  all  of  these  structures  by  examining  her  own  mouth  with  the 
aid  of  a  hand-mirror  and  a  good  light. 


124  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

Salivary  glands. — The  digestive  fluid  of  the  mouth  is  called 
saliva.  It  is  secreted  by  the  salivary  glands,  three  in  number  on 
each  side— the  parotid,  submaxillary,  and  sublingual. 

The  parotid  gland  is  situated  in  front  of  and  below  the  ear, 
and  has  a  duct  about  two  inches  long  {Stenson's  duct)  which  runs 
forward  to  open  into  the  mouth  opposite  the  second  molar  tooth  of 
the  upper  jaw,  piercing  the  buccinator  muscle.  It  secretes  an  abun- 
dant watery  fluid. 

The  surface  line  of  Stenson's  duct  is  drawn  from  the  lobe  of  the  ear  to  the 
middle  of  the  upper  lip. 

The  submaxillary  gland  lies  under  the  angle  of  the  jaw,-  opening 
into  the  floor  of  the  mouth  close  to  the  frenum,  by  Wharton's  duct. 
It  secretes  a  thicker  fluid  than  the  parotid  gland. 

The  sublingual  gland  lies  in  the  (anterior)  floor  of  the  mouth 
and  opens  under  the  tongue  near  the  frenum,  by  several  small 
ducts.     This  also  secretes  a  thicker  fluid. 

The  fluid  which  is  constantly  present  in  the  mouth  and  com- 
monly called  saliva,  is  a  mixture  of  the  secretion  of  the  salivary 
glands  and  the  mucous  glands  of  the  mouth. 

The  reaction  of  the  saliva  is  alkaline.  The  enzyme  or  ferment 
of  saliva  is  ptyalin. 

The  Pharynx. 

The  pharynx,  or  throat,  receives  the  food  from  the  mouth.  It 
occupies  a  space  in  front  of  the  spinal  column  from  the  base  of  the 
skull  to  the  fifth  cervical  vertebra,  its  roof  being  formed  by  the  body 
of  the  sphenoid  bone,  joined  to  the  occipital.  The  walls  of  the  pharynx 
consist  of  three  pairs  of  muscles  called  the  constrictor i> — upper,  middle, 
and  lower,  strengthened  by  a  fibrous  layer  and  lined  with  mucous 
membrane. 

The  illustration  shows  that  the  constrictors  are  flat  muscles  attached  at  the 
sides  to  the  structures  in  front  of  the  phar3mx.  Thus,  from  above  downward, 
their  origin  is  on  the  pterygoid  process,  a  special  ligament,  the  mandible,  side  of 
the  tongue,  hyoid  bone,  thyroid  and  cricoid  cartilages.  The  fibers  all  join  a 
fibrous  line,  or  raphe,  at  the  back,  which  is  suspended  from  the  base  of  the 
occipital  bone.     This  is  their  insertion. 

By  due  contraction  of  these  muscles  the  food  is  grasped  and 
pressed  downward  into  the  esophagus.  They  are  composed  of 
striated  or  voluntary  muscle  fibers. 


THE    PHARYNX. 


■125 


The  upper  part  of  the  pharynx  is  behind  the  nose  and  is  called 
the  nasal  part,  or  naso-pharynx.  The  middle  part  is  behind  the 
Tnonihaindis,  calledihe  oral  pari,  or  oro-pharynx.  (It  is  this  part  which 
we  see  when  looking  directly  into  the  throat.)  The  lower  part 
is  behind  the  larynx  and  is  called  the  laryngeal  part,  or  the  laryngo- 
pharynx. 

The  openings  of  the  pharynx  are  seven  in  number:  the  two 
choancB  (posterior  nares)   communicating  with  the   nose;  the  two 


Orbic.  oris  muscle "^^-^  ^u'^'^"^'^''^'"'        ^^^ 


Special  ligament 


Mylo-hyo.d  muscle 
Hyoid  bone 

Thyroid  cartilage 


Cricoid  cartilage 
Trachea 


Esophagus 


.    Fig.  97. — The  Pharynx  (Holden). 


auditory  {Eustachian)  tubes  communicating  with  the  ears,  and  the 
isthmus  of  the  fauces,  communicating  with  the  mouth.  Below,  it 
communicates  with  the  larynx  (the  opening  being  guarded  b^  the 
epiglottis),  and  opens  into  the  esophagus. 

The  food  passes  through  the  oro-pharynx  and  laryngo-pharynx, 
the  naso-pharynx  being  an  air-passage. 

In  the  roof  of  the  pharynx  is  a  small  mass  of  lymphoid  tissue  called  the 
pharyngeal  tonsil. 


126 


anatomy  and  physiology  for  nurses. 
The  Esophagus. 


The  esophagus  (Figs.  97,  98)  begins  at  the  lower  end  of  the 
pharynx  and  extends  downward  in  the  neck  in  front  of  the  spinal 
column,  to  pass  into  the  thorax.     It  finally  comes  forward  in  front 


Fig.  98. — Showing  Situation  of  Pharynx  behind  Nose,  Mouth,  and  Larynx 
(from  Deaver's  "Surgical  Anatomy"). 
b,  a,  c,  s,  d,  e,  Turbinal  bones  and  meatuses  of  the  nose;  g,  i,  tongue;  h,  posterior 
palatine  arch;  y,  anterior  palatine  arch;  k,  hyoid  bone;  j,  mylo-hyoid  muscle  (floor  of 
mouth);  m,  thyro-hyoid  membrane;  n,  ventricle  of  larynx;  p,  q,  r,  sphenoid  bone  and 
sphenoidal  sinus;  v,  hard  palate;  w,  soft  palate;  x,  uvula;  z,  tonsil;  i,  naso-pharynx;  u, 
orifice  of  auditory  tube;  aa,  oro-pharynx;  dd,  laryngo-phar}'nx;  bb,  epiglottis;  ee,  upper 
portion  of  larynx;  gg,  vocal  bands;  ^,  false  vocal  bands;  hh,  lower  part  of  larynx;  ii, 
cricoid  cartilage;  jj,  trachea. 

of  the  aorta,  passes  through  the  diaphragm,  and  terminates  in  the 
stomach.  It  is  a  tube  about  nine  inches  long,  having  two  ^layers 
of  muscles  (circular  within,  longitudinal  without)  and  lined  with 
mucous  membrane.  By  contraction  of  the  different  muscles  from 
above  downward  the  food  is  passed  along  to  the  stomach. 


ESOPHAGUS. 


127 


The  esophagus  lies  at  first  immediately  behind  the  trachea.  The 
upper  part  is  composed  of  striated,  or  voluntary  muscle  like  that  of  the 
pharynx;  in  the  lower  part  the  muscle  is  non-striated,  or  involuntary , 
like  the  stomach. 

At  the  termination  in  the  stomach,  the  circular  fibers  are  most 
numerous,  forming  the  cardiac  sphincter  which  prevents  the  return  of 
stomach  contents. 


Aorta 


Celiac  artery 
Gastric  arter\ 


Artery 
to  duo- 
denum ^ 
Head  of 
pancreas 


Fig.  99. — The  Stomach  and  Spleen  (Morris). 

The  remaining  organs  of  digestion  are  contained  in  the  abdomi- 
nal cavity,  which  is  lined  with  a  serous  sac  or  membrane  called 
peritoneum  (see  p.  299) .  These  organs  are  developed  from  an  original 
straight  tube  behind  the  peritoneum.  Therefore,  as  they  grow,  they 
press  forward  against  it  and  get  a  covering  which  is  called  their 
serous  layer.  Their  muscular  coats  are  all  involuntary  or  unstriped 
muscle. 


The  Stomach. 

The  stomach  (gastcr,  Fig.  99)  is  in  the  epigastric  region  of  the 
abdomen  just  below  the  diaphragm.  Shape  and  size:  like  a  curved 
flask,  ten  to  twelve  inches  long  and  six  to  eight  wide  at  the  lajger  end, 


128 


ANATOMY  AND   PHYSIOLOGY   FOR  NURSES. 


which  is  turned  toward  the  left  side.     Average  capacity:  five  pints 
in  distension;  two  pints  when  moderately  filled. 

The  stomach  has  two  surfaces,  two  borders,  two  extremities  and 
two  orifices. 

The  surfaces  are  the  anterior — looking  slightly  upward;  and  the 
■posterior — looking  slightly  downward. 

The  borders  are  usually  called  curvatures;  the  upper  border  is  the 
lesser  curvature  (about  five  inches  in  length);  the  lower  border  is 
the  greater  curvature  (about  twenty  inches  in  length). 

The  left  extremity  is  the  expanded  portion  called  the  fundus  of 

the  stomach  (also  the  greater  cul-de- 
sac),  and  the  cardiac  end  (from  its 
nearness  to  the  heart). 

The  right  extremity  is  called  the 
pyloric  extremity.  It  is  just  below 
the  liver. 

The  orifices  are  at  the  extremities. 
At  the  left  is  the  esophageal  orifice 
guarded  by  the  sphincter  of  the  cardia; 
at  the  right  is  the  pyloric  orifice, 
guarded  by  the  sphincter  of  the 
pylorus  or  "gate-keeper." 

The  coats  or  tunics  of  the  stom- 
ach are  four  in  number — mucous,  sub- 
mucous, muscular,  and  serous. 

The  mucous  layer,  or  mucosa,  is 
the  innermost  layer.  It  is  pink  in 
color  but  becomes  bright  red  when  food  is  present,  from  the 
increased  blood-supply  necessary  for  digestion.  It  lies  in  folds,  or 
rugce,  running  from  one  extremity  to  the  other — the  longitudinal 
folds.  This  layer  contains  the  gastric  glands  which  secrete  the 
gastric  juice  and  pour  it  through  their  ducts  into  the  stomach. 

The  gastric  glands  are  tubular  in  form,  microscopic  in  size,  and 
very  numerous  (their  number  is  estimated  at  5,000,000).  They 
differ  markedly  in  the  two  portions  of  the  stomach.  The  cardiac 
glands  secrete  the  digestive  ferments,  pepsin  and  rennin,  while 
the  pyloric  glands  secrete  mucus  also  (Fig.  100). 

The  reaction  of  the  gastric  juice  is  acid  (owing  to  hydrochloric 
acid). 


v;^- 


Fig.  100. — Section  of  Pyloric 
Glands  from  Human  Stom.ach. 
a.  Mouth  of  gland  leading  into 
long,  wide  duct  (6),  into  which 
open  the  terminal  di\'isions.  c. 
Connective  tissue  of  the  mucosa 
(after  Piersol). 


THE    STOiMACH.  1 29 

The  suhmucosa  is  a  network  of  connective  tissue  next  to  the 
mucous  coat.  It  bears  fine  vessels,  nerves  and  lymphatics,  and 
connects  the  mucous  and  muscular  tunics  together  loosely,  so  that 
when  the  stomach  is  distended  the  longitudinal  folds  simply  disappear, 
without  injury  to  the  mucous  membrane. 

The  muscular  coat  (or  tunic)  comprises  three  layers  of  non-striated 
muscle:  internal,  middle  and  external.  The  internal  layer  consists 
of  oblique  fibers  (it  is  a  thin  layer  and  is  mostly  confined  to  the 
cardiac  portion).  The  middle  layer  is  a  complete  layer  of  circular 
fibers.  They  are  most  numerous  at  the  extremities  of  the  stomach, 
where  they  form  two  ring-shaped  bundles.  One  is  the  sphincter  of 
the  cardia,  surrounding  the  lower  end  of  the  esophagus  and  the 
cardiac  orifice  of  the  stomach;  the  other  is  the  sphincter  of  the  pylorus, 
which  is  a  strong  ring-muscle  diminishing  the  size  of  the  pyloric 
orifice  so  that  it  is  the  narrowest  portion  of  the  alimentary  tract  (a 
half-inch,  or  3  mm.).  The  external  layer  consists  of  longitudinal 
fibers  (fibers  running  lengthwise)  which  are  continued  from  the 
similar  layer  of  the  esophagus,  and  pass  on  to  those  of  the 
intestine. 

The  serous  coat  (or  tunic)  is  a  portion  of  the  great  serous  mem- 
brane of  the  abdomen,  called  the  peritoneum  (page  299).  The 
two  surfaces  of  the  stomach  are  covered  by  different  layers  of 
peritoneum  which  will  be  described  elsewhere  (page  137). 

The  position  of  the  stomach  is  oblique,  the  pyloric  end 
being  on  a  lower  level  than  the  cardiac.  It  is  also  the  movable 
end. 

The  location  of  the  stomach  is  mostly  in  the  epigastric  region 
(Fig.  106).  It  is  below  the  portion  of  the  diaphragm  which  supports 
the  heart;  behind  it  are  the  largest  artery  and  vein  in  the  body — the 
aorta  and  the  inferior  vena  cava.  The  pyloric  end  extends  under 
the  liver  in  the  right  hypochondrium,  while  the  cardiac  end  is  in  the 
left  hypochondrium,  in  contact  with  the  spleen. 

Clinical  notes. — When  the  stomach  is  empty  it  tends  to  a  vertical  position; 
when  filled,  it  swings  upward  and  forward  to  become  again  oblique.  If  much 
distended,  as  with  gas,  it  embarrasses  the  action  of  the  heart  by  pressure. 

The  infant's  stomach  is  nearly  or  quite  vertical  and  easily  overflows;  its 
capacity  at  birth  is  one  ounce,  reaching  two  ounces  at  about  the  end  of  a 
fortnight. 


130  anatomy  and  physiology  for  nurses. 

The  Intestine. 

The  intestine  or  bowel,  begins  at  the  pyloric  orifice  of  the 
stomach  and  continues  to  the  end  of  the  alimentary  tract.  It  is  from 
twenty-five  to  thirty  feet  in  length  (Fig.  loi). 


Appendix 


Small  in- 
testine 


Fig.  ioi. — The  Intestines  (Morris). 
Large  intestine  thrown  upward,  small  intestine  drawn  to  left. 


Like  the  stomach,  it  is  composed  of  four  coats  or  tunics — mucous ^ 
submucous,  muscular  and  serous. 

The  mucous  coat  is  the  glandular  coat;  that  is,  the  glands  which 
secrete  intestinal  juice  are  imbedded  in  the  mucous  coat,  and  their 
ducts  open  on  its  surface. 


THE    SMALL   INTESTINE. 


131 


In  addition,  small  gland-like  bodies  of  lymphoid  structure  are  scattered 
throughout  this  coat.  They  have  no  ducts.  They  are  probably  lymph  nodules 
— the  so-called  solitary  glands. 

The  submucous  coat  bears  the  fine  vessels  and  nerves  which  supply 
the  mucous  coat.  It  connects  the  mucous  and  muscular  coats 
together. 

The  muscular  coat  comprises  two  layers  (like  the  esophagus) ,  an 
inner  layer  of  circular  fibers,  an  outer  one  of  longitudinal  fibers. 

The  intestine  is  divided  into  the  following  parts: 


Duodenum 
Small  intestine  {   Jejunum        Large  intestine 
Ileum 


Cecum 

Colon 

Rectum 


Ascending 
Transverse 
Descending 


The  Small  Intestine. 

The  small  intestine  is  about  twenty  feet  in  length,  and  about 
two  inches  wide  in  its  upper  (widest)  part.  It  extends  from  the 
stomach  to  the  colon,  beginning  with  the  pyloric  sphincter  in  the 
right  hypochondrium  and  ending  with  the  ileo-colic  sphincter  in  the 
right  iliac  region. 

The  mucous  coat  of  the  small  intestine  forms  circular  folds  (old 
name,  valvulae  conniventes)  which  are  permanent,  that  is,  they  never 
disappear  however  widely  the  bowel  may  be  distended.  They  serve 
to  increase  the  area  of  mucous  membrane  for  purposes  of  digestion 
and  absorption  (Fig.  103). 

The  secreting  glands  which  are  found  in  every  part  of  the  small 
intestine  are  called  the  intestinal  glands  (or  intestinal  follicles,  or 
glands  of  Lieberkiihn) .  They  are  tubular  in  shape,  and  secrete  the 
greater  portion  of  the  intestinal  juice.  The  ferment  of  the  glands 
of  Lieberkiihn  is  not  known.  The  reaction  of  the  secretion  is 
alkaline. 

The  entire  mucous  coat  is  covered  with  tiny  projections  hair- 
like in  size  (from  1/2  to  i  mm.  long)  called  villi,  which  give  it  a 
velvety  appearance  (Fig.  102). 

In  the  midst  of  each  villus  is  a  minute  lymph-capillary,  surrounded  by  a  fine 
network  of  blood-vessels  and  lymph-spaces,  the  whole  covered  by  a  layer  of  the 
special  epithelium  of  the  intestine. 


132 


ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 


The  villi  are  absorbing  structures  or  absorbents.  (They  may 
be  demonstrated  in  a  good  light  by  laying  a  piece  of  intestinal  wall 
in  a  shallow  tray  of  clear  water;  the  water  will  float  their  free 
extremities.) 

The  muscular  coat  is  in 
two  layers — circular  within, 
longitudinal  without — pretty 
evenly  distributed. 

The  serous  coat  covers  all 

except  a  portion  of  the  first 

division  (see  duodenum). 

The  duodentim  is  the  first 

.    division  of  the  small  intestine 


Fig.  I02. — Section  or  Injected  Small 
Intestine  of  Cat. 

a,  b.  Mucosa  g.  Villi,  i.  Their  absorbent 
vessels,  h.  Simple  follicles,  c.  Muscularis 
mucosse.  j.  Submucosa.  g.  e.  Circular  and 
longitudinal  layers  of  muscle.  /.  Fibrous 
coat.  All  the  dark  lines  represent  blood- 
vessels filled  with  the  injection  mass 
(Piersol). 


Fig.  103. — Circular  Fold  or  Val- 
vule Conniventes    (Morris). 


(Fig.  104).  (It  is  about  ten  inches  long,  begins  at  the  pyloric  end  of 
the  stomach,  curves  upward  and  backward  to  make  a  horse-shoe 
bend  to  the  right  and  downward,  and  then  continues  across  to  the 
left  side  of  the  spinal  column  thus  making  a  superior,  descending 
and  inferior  part.) 

The  circular  folds  of  the  mucous  coat  begin  in  the  lower  portion 
and  are  unusually  large. 


THE    SMALL    INTESTINE. 


133 


There  are  special  glands  in  the  duodenum  not  found  elsewhere, 
called  duodenal  glands  or  Brunner's  glands;  they  furnish  a  portion  of 
the  intestinal  juice. 

Note. — The  inferior  part  of  the  duodenum  is  behind  the  peritoneum,  this 
fart  has  no  serous  coat. 

20  12    19 


Fig.  104. — Liver,  Paxcreas,  Duodenum,  Spleen  and  Kidneys,  i,  2,  3,.  Duode- 
num. 4,  4,  5,  6,  7,  7,  S.  Pancreas  and  pancreatic  ducts.  Q,  10,  11,  12,  13.  Liver. 
14.  Gall  bladder.  15.  Hepatic  duct.  16.  Cystic  duct.  17.  Commonduct.  18.  Portal 
vein.  iQ.  Branch  from  the  celiac  axis.  20.  Hepatic  artery.  2t.  Coronary  artery 
of  the  stomach.  22.  Cardiac  portion  of  the  stomach.  23.  Splenic  arter\'.  24. 
Spleen.  25.  Left  kidney.  26.  Right  kidnev.  Section  of  pancreas  to  show  ducts. 
Liver  turned  upwards  and  stomach  removed  to  show  duodenum. 


The  jejunum  is  the  second  division  of  the  small  intestine — 
so  named  because  it  is  found  empty.  It  possesses  all  of  the  char- 
acteristic structures:  villi,  circular  folds,  intestinal  and  solitary 
glands.     It  lies  in  the  umbilical  and  the  two  lumbar  regions. 

The  Ileiun  is  the  third  division  of  the  small  intestine — so  named 
because  of  its  frequent  twisting.  There  is  no  definite  separation 
between  the  end  of  the  jejunum  and  the  beginning  of  the  ileum. 

The  villi,  circular  folds,  intestinal  glands  and  solitary  glands  are 
all  found  in  the  ileum.  The  circular  folds  diminish  in  size  as  the 
necessity  for  their  presence  grows  less  in  the  lower  portion,  but  the 
solitary  glands  increase  in  size  and  number.     They  are  grouped  into 


134  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

various  oblong  patches,  toward  the  lower  end  of  the  ileum,  the 
Peyer's  patches  or  agminated  glands.  (The  largest  patches  may 
measure  three  inches  in  length.) 

The  reaction  of  the  intestinal  fluids  is  alkaline. 

Clinical  note. — The  solitary  glands  (more  especially  the  Peyer^s 
patches),  become  inflamed  and  ulcerated  in  typhoid  fever. 

The  ileum  ends  in  the  right  iliac  region  by  opening  into  the 
large  intestine.  This  orifice  is  doubly  guarded;  first,  by  two  folds 
of  mucous  membrane  strengthened  by  fibrous  tissue,  called  the 
ileo-cecal  valve;  second,  by  a  circular  muscle  called  the  ileo-colic 
sphincter;  this  is  the  more  important  of  the  two. 

The  Large  Intestine. 

The  large  intestine  is  about  five  feet  long  and  two  and  one-half 
inches  wide  in  the  widest  part.  It  begins  where  the  small  intestine 
ends  (in  the  right  iliac  region),  ascends  through  the  right  lumbar, 
crosses  the  abdomen  in  front  of  the  small  intestine,  descends  to  the 
left  iliac  region,  and  thence  down  through  the  pelvis,  ending  in  front 
of  the  coccyx.     (See  Regions  of  the  Abdomen,  p.  296.) 

The  mucous  coat  is  smooth  and  rather  pale.  No  folds  are 
present,  and  no  villi,  but  the  solitary  and  tubular  glands  are 
numerous. 

The  circular  fibers  of  the  muscular  coat  are  evenly  distributed, 
but  the  longitudinal  fibers  of  the  cecum  and  colon  are  arranged  in 
three  bands,  placed  at  even  distances  apart.  These  bands  are 
shorter  than  the  tube  itself,  therefore  they  gather  it  into  puffs  which 
give  the  bowel  a  sacculated  appearance.  By  this,  the  large  bowel 
may  be  recognized  at  once,  even  should  it  be  really  small  in  actual  size 
in  some  portion  of  its  extent. 

The  serous  coat  covers  the  greater  part  of  the  large  intestine;  the 
exceptions  will  be  noted  later. 

The  four  divisions  of  the  large  intestine  are  the  cecum,  the 
colon,  the  sigmoid  loop,  and  the  rectum  (Figs.  loi,  105). 

The  cecmn,  or  first  division,  is  a  short  pouch  hanging  below  the 
level  of  the  ileocolic  valve  and  presenting  the  opening  of  the  appendix 
verjniformis  or  appendix  ceci.  The  three  longitudinal  bands 
of  the  muscular  coat  meet  at  the  base  of  the  appendix,  which  is  a 
small  tube  three  or  four  inches  long,  attached  to  the  posterior  side  of 


THE    LARGE    INTESTINE. 


135 


the  cecum.  It  often  turns  upward,  quite  as  often  downward,  and 
may  lie  transversely.  It  has  all  four  coats,  with  intestinal  and  soli- 
tary glands,  but  is  of  no  use. 

Clinical  note. — Owing  to  its  small  size  any  substance  which  enters  the 
appendix  is  apt  to  be  retained,  and  if  it  is  of  an  injurious  character  it  will 
cause  appendicitis.  This  disease  is  more  often  caused  by  the  action  of 
harmful  bacteria  than  the  celebrated  cherry-stone.  Small  intestinal  worms 
have  been  found  within  the  appendix. 


Fig.  105. — I'he  Large  Intestine. 

The  small  intestine  and  its  vessels  are  drawn  to  the  right  to  show  the  sigmoid  colon  and 

the  rectum.     The  transverse  colon  is  thrown  upward  (Morris). 


The  ilio-cecal  valve  consists  of  two  folds  of  mucous  membrane 
with  muscle  fibers  between  the  layers.  They  are  placed  at  the  end 
of  the  ilium  where  it  opens  into  the  colon,  and  project  toward  each 
other,  leaving  only  a  slit-like  passage. 

The  colon  begins  at  the  ilio-cecal  valve.     The  first  part,  or 


136  ANATOMY  AND    PHYSIOLOGY   FOR    NURSES. 

ascending  colon,  passes  upward  in  the  right  lumbar  region.  After 
making  a  bend  under  the  liver — the  right  colic  flexure  (or  hepatic 
flexure),  it  becomes  the  transverse  colon,  which  hangs  in  a  loop  across 
the  abdomen  in  front  of  the  small  intestine.  Another  bend  occurs 
under  the  spleen,  the  left  colic  flexure  (or  splenic  flexure);  thence 
.  the  descending  colon  passes  downward  in  the  left  lumbar  region  to  the 
left  iliac  fossa.  Here  it  makes  an  S-shaped  or  sigmoid  bend  and 
becomes  the  so-called  sigmoid  colon.  It  then  enters  the  pelvis  to 
become  the  rectum. 

Surgical  note. — The  ascending  colon  lies  so  close  to  the  posterior  abdominal 
wall  that  there  is  no  peritoneum  behind  it,  and  the  descending  colon  also  is  bare  in 
a  narrow  strip  at  the  back,  consequently  the  surgeon  may  take  advantage  of  this 
condition  to  open  the  colon  without  wounding  the  peritoneum,  in  the  operation 
called  lunibo-colotomy. 

The  rectum  is  about  five  to  seven  inches  long,  very  distensible, 
and  so  called  because  it  has  no  convolutions,  but  simply  follows  the 
curve  of  the  pelvic  wall,  lying  in  front  of  the  sacrum  and  coccyx.  In 
the  last  inch  or  inch  and  a  half  it  bends  backward  {perineal flexure) 
to  pass  the  tip  of  the  coccyx.  This  is  the  anal  canal,  and  it  ends  at 
the  opening  called  the  anus  (Fig.  105). 

The  portion  above  the  anal  canal  is  the  widest  pars — the  rectal 
pouch. 

The  mucous  membrane  of  the  rectum  is  red,  and  usually  presents 
two  or  three  special  folds  about  two  or  three  inches  above  the  anus, 
called  the  rectal  folds,  or  Houston's  valves. 

The  largest,  a  permanent  fold,  is  on  the  right  side  about  two  and  one-half 
inches  above  the  anus  and  called  the  third  sphincter.  Two  smaller  ones,  not 
permanent,  are  on  the  left  side,  above  and  below  the  former. 

The  muscular  coat  has  the  two  layers,  circular  and  longitudinal. 
The  peritoneal  coat  covers  the  front  and  sides  of  the  upper  part  only. 

The  reaction  of  the  fluids  in  the  large  intestine  is  alkaline. 

Sphincters  of  the  anus. — The  circular  fibers  around  the  anal 
canal  form  the  internal  sphincter. 

The  external  sphincter  is  a  flat  circular  muscle  just  under  the 
skin  around  the  anus.  The  function  of  the  sphincters  is  to  guard 
and  control  the  anus. 

Clinical  note.— The  point  of  a  syringe  should  be  passed  in  an  upward  and 
forward  direction  through  the  anal  canal,  and  then  turned  backward. 


THE    MESENTERY.       THE    PANCREAS,  I37 

Resume. 

The  alimentary  tract  begins  with  the  mouth  and  ends  with  the  large  intestine, 
passing  through  the  head,  neck,  thorax,  and  pelvis.  It  is  practically  a  long  tube 
of  mucous  membrane  surrounded  by  layers  of  muscle  and  held  to  them  by 
connective  tissue.  The  mucous  membrane  contains  glands  which  secrete  the 
digestive  fluids.  The  muscle  layers  pass  the  food  along,  that  it  may  be  acted 
upon  in  all  portions  of  the  tract;  and  wherever  free  motion  accompanies  the 
digestion  of  the  food,  a  serous  layer  is  added  outside  of  all  to  prevent  friction. 

The  digestive  fluid  of  the  stomach  is  acid;  in  all  other  parts  it  is  alkaline. 

Peristalsis  Is  the  name  given  to  the  peculiar  motion  of  the 
stomach  and  intestine  during  the  passage  of  their  contents.  The 
circular  fibers  compress  the  food  and  at  the  same  time  the  longitudi- 
nal fibers  shorten  the  tube.  This  action  goes  on  from  above  down- 
ward, causing  a  sort  of  worm-like  movement  which  is  described  as 
peristalsis,  or  peristaltic  movement. 

The  mesentery  is  the  fold  of  peritoneum  which  holds  the  jeju- 
num and  ileum  in  place.  This  fold  leaves  the  posterior  abdominal 
wall  at  a  line  inclining  downward  to  the  right,  about  five  or  six  inches 
long;  but  it  includes  twenty  feet  of  intestine,  and  therefore  it  is  like 
a  very  full  ruffle  twenty  feet  in  length  with  a  band  of  six  inches. 
The  vessels  and  nerves  of  the  intestine  lie  between  the  layers  of  the 
mesenteric  fold. 

Any  fold  of  peritoneum  which  connects  a  portion  of  intestine  to  the  wall  of 
the  trunk  is  a  mesentery.  The  meso-colon  connects  the  colon  with  the  abdominal 
wall;  the  meso-rectum  connects  the  rectum  with  the  pelvic  wall;  the  large  mesen- 
tery holds  the  ilium  and  jejunum  to  the  posterior  abdominal  wall. 

An  omentum  is  a  fold  of  peritoneum  connected  with  the  stomach.  The 
greater  omentum  hangs  from  the  greater  curvature;  the  lesser  omentum  connects 
the  lesser  curvature  with  the  liver  (being  called  the  gastrohepatic  omentum) ;  and 
the  gastrosplenic  omentum  connects  the  stomach  and  spleen.  Two  layers  of 
peritoneum  pass  from  the  under  surface  of  the  liver  to  the  lesser  curvature  of  the 
stomach,  forming  the  lesser  omentum.  They  then  separate  to  enclose  the  sur- 
faces of  the  stomach,  making  its  serous  coat.  They  come  together  again  at  the 
greater  curvature  and  hang  down  in  the  shape  of  a  large  serous  sac  with 
double  walls,  the  greater  omentum,  which  hangs  in  front  of  the  small  intestine. 

Note, — The  transverse  meso-colon  usually  becomes  adherent  to  the  greater 
omentum  (Fig.  106). 

The  Pancreas. 

The  pancreas  (Figs.  104,  105)  is  a  gland  situated  behind  and 
below  the  stomach.     It  is  about  seven  inches  long  and  somewhat 


138 


ANATOMY  AND   PHYSIOLOGY    FOR   NURSES. 


resembles  a  hammer  in  shape,  the  head  being  turned  to  the  right 
and  lying  within  the  curve  of  the  duodenum,  the  body  crossing  to  the 
left,  and  the  tail  reaching  the  spleen.     It  secretes  an  abundant 


Fig.  io6. — The  Abdominal  Organs  (Gerrish,  after  Testut). 
The  liver  is  turned  upward  to  show  the  inferior  surface  with  the  gall-bladder.     The 
vessels  entering  and  leaving  the  porta  are  also  seen,  the  lesser  omentum  having  been 
removed. 


alkaline  pancreatic  fluid,  conveyed  by  the  pancreatic  duct  to  the  duo- 
denum. The  duct  opens  (with  the  common  bile  duct)  into  the  duo- 
denum about  four  inches  from  the  pylorus. 


THE    LIVER.  139 

The  three  pancreatic  ferments  are  amylopsin,  trypsin  and  steap- 
sin  (for  starch,  proteid  and /a/)  ('see  page  147). 

The  Liver. 

The  liver  (Fig.  106)  is  the  largest  abdominal  organ,  and  the 
largest  gland  in  the  body.  Its  normal  weight  is  between  three  and 
four  pounds  (1300  to  1700  grams).  It  is  underneath  the  diaphragm, 
in  the  right  upper  portion  of  the  abdomen,  the  thin  left  lobe  extend- 
ing across  the  epigastric  region  above  the  stomach.  Its  general 
shape  is  that  of  a  wedge,  much  thicker  at  the  right  side  than  the  left, 
and  with  the  thin  edge  turned  forward.  The  upper  surface  is  con- 
vex, and  marked  off  by  a  ligament  into  two  lobes,  right  and  left.  The 
lower  surface  is  divided  by  five  fissures  into  five  lobes.  The  largest 
fissure  is  the  transverse,  the  porta  {or  gate)  for  the  passage  of  vessels,^ 
nerves  and  ducts. 

The  liver  secretes  a  yellow  alkaline  fluid  called  bile  which  is 
conveyed  through  the  porta  two  by  ducts,  the  right  hepatic  and 
left  hepatic;  these  unite  to  form  one,  the  hepatic  duct  proper, 
which  is  soon  joined  by  the  cystic  duct  from  the  gall-bladder. 

The  gall-bladder  occupies  a  fissure  on  the  inferior  surface  of 
the  liver.  It  is  a  pear-shaped  sac  three  or  four  inches  long,  of 
fibrous  tissue  and  muscle  fibers  lined  with  mucous  membrane  and 
partially  covered  with  peritoneum.  It  contains  a  variable  quantity 
of  bile  (or  "gall ")  in  reserve.  The  only  opening  of  the  gall-bladder 
is  for  the  cystic  duct,  which  joins  the  hepatic  to  form  the  common 
bile-duct,  or  ductus  communis  choledochus.  This  opens  into  the 
doudenum  with  the  pancreatic  duct  (Fig.  104,  106). 

Note. — The  production  of  bile  is  continuous;  its  flow  into  the 
intestine  is  intermittent.  It  appears  in  the  duodenum  only  during 
the  process  of  digestion;  in  the  interval  it  is  stored  in  the  gall-bladder. 

The  substance  of  the  interior  of  the  liver  is  composed  of  secreting 
cells  called  hepatic  cells,  grouped  in  lobules,  with  a  multitude  of 
blood-vessels,  lymphatics  and  nerves,  supported  by  connective  tissue. 

.\n  hepatic  lobule  measures  only  about  a  millimeter  (2V  of  an  inch)  in 
width.  Between  its  cells  there  is  a  fine  network  of  hepatic  and  portal  blood- 
vessels, and  lymph  spaces;  also  bile  passages.  The  blood-vessels  empty  into 
hepatic  veins;  the  lymph  spaces  form  lymph  vessels,  and  the  bile  passages  lead 
to  small  bile  ducts  which  unite  and  reunite  to  form  the  hepatic  ducts. 

'  Lymph  vessels  and  hepatic  artery.     Hepatic  veins  take  a  different  route. 


I40  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


Vessels  passing  through  the  porta  (or 
transverse  fissure)  of  the  Uver: 


„   ,     .  f  Hepatic  artery. 

Entering       <  . 

[  Portal  vein 

{  Two  hepatic  ducts. 

[  Lymphatics. 

All  of  the  hepatic  veins  leave  the  liver  at  the  back,  opening  at  once  into 

a  larger    vein    running  to  the  heart  (the  inferior  vena  cava).     The  great 

quantity  of  venous  blood  which  the  liver  contains  gives  to  it  its  dark  color. 

Five  ligaments  of  the  liver  hold  it  in  place  attaching  it  to  the  dia- 
phragm and  abdominal  wall — the  round,  the  broad,  the  coronary, 
and  two  lateral. 

The  round  ligament  is  a  cord  (the  remains  of  the  umbilical  vein) 
inclosed  in  the  broad,  which,  with  the  lateral  and  coronary,  is  of 
peritoneum.  It  is  the  broad  ligament  which  connects  the  superior 
surface  of  the  liver  with  the  diaphragm  and  is  therefore  called  the 
suspensory  ligament.  It  also  marks  off  the  right  from  the  left  lobe 
on  that  surface. 


CHAPTER  IX. 
FOODS  AND  DIGESTION. 

FOODS. 

The  human  body  is  a  machine  constantly  in  motion;  therefore, 
its  cells  continually  use  up  their  force,  and  continually  need  renewing. 
The  material  for  this  renewal  is  supplied  by  the  food  which  we  eat, 
and  as  the  various  parts  of  the  body  are  composed  of  quite  different 
tissues,  so  the  food  is  of  a  mixed  character. 

The  composition  of  the  tissues  requires  that  for  their  growth  and 
lepsiir  four  classes  of  food  principles  must  be  included  in  the  dietary. 

1.  Proteids. 

2.  Carbohydrates  (sugars  and  starches). 

3.  Fats. 

4.  Mineral  salts. 
In  the  body: — 

1.  Proteids  are  found  in  all  tissues  of  the  body,  most  abundantly 
in  the  blood,  as  serum  albumin,  fibrinogen,  hemoglobin;  in  the 
lymph,  as  serum  albumin;  in  the  muscles,  as  myosinogen;  in  the  milk, 
as  caseinogen. 

2.  Carbohydrates  (or  sugars  and  starches)  are  found  principally 
in  the  blood,  as  dextrose;  in  the  liver  and  muscles,  as  glycogen;  in  the 
milk,  as  lactose.  (Glycogen  is  an  animal  starch  formed  within  the 
body,  the  others  are  sugars.  Dextrose  and  grape  sugar  are  the 
same.) 

3.  Fats  are  found  in  subcutaneous  fascice  and  around  organs, 
as  adipose  tissue;  in  milk,  as  emulsion;  in  blood  cells,  nerves,  lymph, 
as  lecithin;^  in  bones,  as  marrow. 

4.  Mineral  salts  are  found  in  all  tissues  and  fluids  of  the  body, 
mfiuids  especially,  as  water;  in  bones  and  teeth  especially,  as  lime 
salts;  in  muscle,  nerves  and  blood,  as  potassium  salts;  in  all  tissues,  as 
sodium;  in  red  blood  cells,  as  iron. 

The  blood  must  draw  from  all  four  classes  oi  food  principles 
for  its  composition,  since  it  bears  to  all  parts  of  the  body  their 
food.     "The  blood  is  the  life." 

*  Probably  derived  from  nerve  tissue  in  the  body 

141 


142  ANATOMY  AND    PHYSIOLOGY   FOR    NURSES. 

In  the  dietary: 

Proteids  must  be  supplied  to  all  tissues.  They  are  the  tissue 
builders.  They  may  be  obtained  from  meats,  as  myosin  and  albu- 
min; eggs,  as  albumin  from  white,  vitelline  from  yolk;  grains,  as 
gluten;  vegetables,  as  vegetable  albumin  (peas,  beans,  corn,  etc.). 

Starches  and  sugars  are  utilized  by  liver  and  muscles  and  are 
probably  the  principal  sources  of  muscle  energy.  They  and  their 
compounds  are  easily  oxidized,  that  is,  combined  with  oxygen.  They 
are  obtained  from /rw^'/^,  as  sugar  (dextrose);  from  milk,  as  lactose; 
from  cereals,  peas,  beans  and  potatoes,  as  starch;  from  sugar  cane, 
beets,  etc.,  as  cane  sugar  or  saccharose. 

Fats  are  needed  for  the  marrow  of  bones,  as  protective  coverings, 
and  to  fill  in  spaces  between  organs.  Also  to  preserve  body  heat 
as  well  as  to  produce  it. 

They  are  obtained  from  animal  foods,  from  milk,  from  grains, 
corn,  oats,  etc.,  and  formed  in  the  body  from  sugars. 

Mineral  salts  are  needed  everywhere,  although  in  small  quan- 
tities, as  a  rule. 

Water  is  the  most  important,  being  indispensable  to  life.  It  con- 
stitutes nearly  three-fourths  of  the  body  weight  and  is  universally 
present,  even  in  the  hardest  tissues  {e.g.,  enamel  of  teeth).  Its  most 
important  uses  are: 

1.  To  hold  in  solution  the  nutritive  principles  and  make  it  pos- 
sible that  the  tissues  may  absorb  them. 

2.  To  sweep  away  the  waste  products  to  organs  which  can  excrete 
them. 

It  is  obtained  from  all  foods,  but  must  be  added  in  bulk  (Small 
quantities  are  formed  within  the  body.) 

Sodium  chloride  stands  next  in  importance.  In  an  unexplained 
way  it  is  necessary  to  the  normal  activities  of  the  tissues.  It  must 
be  added  to  other  foods. 

Phosphate  of  calcium  is  needed  by  bones  and  teeth,  forming  a  large 
proportion  of  their  weight.  It  is  the  most  abundant  mineral  salt 
(next  to  water).  It  is  obtained  from  vegetables,  grains  and  proteid 
foods. 

Iron  is  a  necessary  constituent  of  red  blood  cells,  in  hemoglobin. 
It  is  obtained  from  meats  and  other  animal  foods  and  some  vegetables. 

Atmospheric  Air  as  Food. — Sugars,  starches  and  fats  consist  of 
carbon,  hydrogen  and  oxygen  (CHO).     The  proteids  add  nitrogen 


FOODS   AND    DIGESTION.  I43 

(CHNO)  and  a  little  sulphur  (CHNOS) .  (The  formulae  are  omitted, 
the  symbols  being  sufficient  for  our  purpose.)  These  elements  are 
all  furnished  in  suitable  quantities  by  the  food  as  described,  except 
oxygen.  This  is  obtained  in  great  measure  from  the  air  we  breathe, 
which  consists  of  nitrogen  and  oxygen. 

This  atmospheric  nitrogen  does  not  form  combinations  with  other  elements;  it  is 
thought  to  serve  only  as  a  diluent  for  oxygen. 

The  oxygen  is  the  important  element.  It  passes  from  the  lungs 
into  the  blood  and  is  carried  by  the  red  cells  to  the  tissues  at  large. 
(This  is  further  described  in  Chapter  XIII.) 

With  the  exception  of  oxygen,  (which  is  introduced  into  the 
system  through  the  lungs),  food  enters  the  system  through  the  ali- 
mentary tract,  being  here  prepared  for  the  uses  for  which  it  is  designed, 
by  the  process  of  digestion. 

Different  articles  of  food  should  be  combined  in  such  way  as  to 
secure  proper  adjustment  of  food  principles  to  body  needs. 

For  example :  with  meats,  vegetables  should  be  served  rather  than 
milk  or  eggs. 

Avoid  a  number  of  starchy  vegetables  in  the  same  meal.  For 
example:  to  potatoes,  or  rice,  or  hominy,  add  green  vegetables,  as 
string-beans,  spinach,  celery,  etc. 

There  is  good  reason  for  adding  butter  to  bread  and  oil  to  salad, 
as  neither  flour  nor  green  things  contain  fat. 

Milk  is  well  combined  with  starchy  food,  having  within  itself 
both  proteids  and  fat.  Eggs  can  take  the  place  of  meat  to  a  large 
extent;  they  may  be  combined  with  milk. 

The  shell  or  husk  of  grain  contains  certain  mineral  salts  which  are 
about  our  only  source  of  silica  for  the  hair  and  teeth;  therefore — 
give  whole  grains  to  growing  children. 

Whole-wheat  flour,  and  ripe  beans  or  peas,  contain  proteid  in  a 
vegetable  form;  ripe  corn  (cornmeal)  contains  more  fat  than  other 
cereals,  and  protein  as  well. 

All  vegetables  contain  a  varying  amount  of  fiber  which  is  indi- 
gestible, but  which  is  beneficial,  since  it  serves  to  prevent  the  con- 
centration of  waste  matters  in  too  small  bulk  for  the  action  of  the 
large  intestine.    Three  reasons  for  cooking  food  are  as  follows: — 

Cooked  starch  is  more  easily  digested  than  raw,  for  the  following 
reasons :  The  change  of  starch  into  sugar  requires  that  it  should  first 
be  hydraled,  that  is,  water  must  be  added  to  it.     It  exists  in  granules 


144  ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 

and  each  granule  of  starch  has  a  covering  of  cellulose  which  is 
practically  indigestible.  In  the  process  of  cooking,  the  boiling 
water  penetrates  to  the  granule,  uniting  with  it  and  causing  it  to  free 
itself  from  the  envelope.  At  once  it  can  be  acted  upon  by  ptyalin  if 
in  the  mouth,  or  amylopsin  if  in  the  small  intestine.  With  raw 
starch,  hydration  goes  on  slowly  or  not  at  all.  Imperfectly  cooked 
starch  is  unwholesome  for  the  same  reason. 

Vegetables  also  should  be  thoroughly  cooked  both  on  account  of 
the  starch  which  they  contain,  and  the  fibrous  material,  which  needs 
partial  disintegration  by  heat. 

Meats  are  more  easily  digested  if  cooked  long  enough  to  soften 
their  connective  tissue  fibers.  By  heat  these  are  converted  into  a 
gelatinous  substance  which  can  be  disposed  of  by  pepsin  and  trypsin. 

Clinical  note.- — The  "  scraped  beef  sandwich"  so  often  ordered  for  patients, 
contains  the  substance  of  the  muscle  cell  alone,  which  has  been  scraped  away 
from  the  connective  tissue  fiber;  it  is  easily  digestible  because  it  may  at  once  be 
converted  into  peptone  without  the  necessity  for  first  digesting  the   tougher 


DIGESTION. 

Digestion  is  the  process  of  so  changing  the  food  that  its  nutritive 
parts  may  be  absorbed  into  the  system. 

The  organs  described  in  Chapter  VHI  are  so  connected  and 
arranged  that  they  receive  and  act  in  consecutive  order  upon  the 
food,  causing  a  series  of  changes  which  result  in  separating  nutriment 
from  waste  and  preparing  it  for  absorption,  expelling  the  waste  from 
the  system. 

The  process  of  digestion  begins  in  the  mouth  and  continues 
throughout  the  small  intestine.  The  food  is  first  divided  into  small 
pieces  by  means  of  the  teeth.  This  is  mastication.  At  the  same 
time  it  is  mixed  with  saliva;  this  is  hydration  and  insalivation. 

By  the  act  of  swallowing,  the  softened  mass  is  passed  into  the 
pharynx  and  down  through  the  esophagus  to  the  stomach.  This  is 
deglutition.  (The  soft  palate  prevents  it  from  going  upward  to  the 
nose,  and  the  epiglottis  prevents  it  from  entering  the  larynx.) 

The  stomach  now  takes  charge.  The  mass  is  compressed  and 
moved  about  by  the  layers  of  the  muscular  coat  until  it  is  thoroughly 
saturated  with  gastric  juice,  and  becomes  a  pale  yellowish  fluid 
called  chyme.     As  fast  as  this  is  accomplished,  the  pylorus,  or  gate- 


FOODS   AND    DIGESTION.  I45 

keeper,  allows  it  to  go  through  into  the  duodenum,  where  it  meets  the 
intestinal  and  pancreatic  juices,  and  bile. 

Continuing  through  the  small  intestine  it  loses  in  increasing  meas- 
ure its  fluid  and  nutritious  portions,  and  in  the  large  intestine  it  is 
still-further  reduced  to  waste  alone,  which  is  expelled  from  the  body. 

The  food  is  subjected  to  two  sorts  of  processes  in  each  division 
of  the  alimentary  tract;  the  first  is  mechanical,  the  second  chemical. 

The  first  occurrence  which  follows  the  introduction  of  food,  is  an 
increased  flow  of  blood  to  the  part  and  activity  of  the  secreting  cells 
as  the  food  arrives,  beginning  with  the  secretion  of  saliva.  In  fact, 
the  cells  may  begin  to  work  beforehand,  being  stimulated  by  the 
thought  of  food. 

In  the  mouth  the  mechanical  process  includes  mastication  and 
insalivation.  By  the  teeth  the  food  is  divided,  then  crushed  and 
ground;  at  the  same  time  it  is  softened  by  saliva.  The  parotid  saliva 
does  most  of  this,  being  the  most  abundant;  it  is  poured  into  the 
mouth  just  outside  the  upper  second  molar  and  thus  it  mixes  at  once 
with  the  mass  as  it  is  crushed  and  ground.  Submaxillary  and  sublin- 
gual saliva  contain  much  more  mucin,  and  lubricate  as  well  as  soften 
the  food. 

The  chemical  process  consists  in  the  conversion  of  starch  into 
sugar.  This  is  accomplished  by  ptyalin,  a  ferment  (or  enzyme)  in 
the  saliva.  Starch  is  not  soluble,  therefore,  not  absorbable.  Sugar 
is  both.  Not  all  the  starch  taken  at  one  time  is  digested  in  the 
mouth  for  the  reason  that  it  leaves  the  mouth  too  soon.  (If  it  is  re- 
tained in  the  mouth  for  some  time,  especially  if  mastication  be  con- 
tinued, the  presence  of  the  sugar  thus  formed  will  be  evident  to  the 
taste.) 

Ptyalin  cannot  act  in  acid  fluids:  The  saliva  is  alkaline. 

Being  masticated  and  insalivated  the  food  is  passed  through  the 
pharynx  and  esophagus  into  the  stomach.  The  tongue  presses 
against  the  hard  palate,  thus  giving  the  bolus  (as  the  prepared  mass 
is  called)  an  impulse  toward  the  isthmus  of  the  fauces;  as  it  passes 
through  this  space  the  upper  pharyngeal  constrictor  muscle  grasps  it 
and  passes  it  on — then  the  middle  and  the  lower  constrictors  in  turn 
— and  it  enters  the  esophagus.  (Meanwhile  the  soft  palate  has  pre- 
vented it  from  going  upward  and  the  epiglottis  from  entering  the 
larynx. j 

Through  the  cardiac  sphincter  of  the  esophagus  it  enters  the 


146  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

stomach.  Here  the  mechanical  process  consists  in  the  action  of  the 
muscle  coats,  which  move  the  food  about  that  it  may  be  still  more 
softened  and  thoroughly  mixed  with  gastric  juice.  The  contractions 
of  the  muscles  of  the  stomach  go  on  in  a  wave-like  manner  toward  the 
pylorus.     They  alternately  constrict  and  relax  the  walls  of  the  cavity. 

The  chemical  process  in  the  stomach  consists  in  the  conversion  of 
proteid  substances  into  peptones  by  the  action  of  hydrochloric  acid 
and  pepsin.  Gastric  juice  contains  two  ferments  or  enzymes,  pepsin 
and  rennin.  Pepsin  attacks  the  proteids  after  they  have  been  acidi- 
fied (it  cannot  work  in  alkaline  fluids). 

In  the  digestion  of  meats,  the  acid  softens  the  connective  tissue 
fibers  (which  are  already  partially  gelatinized  by  cooking)  and  thus 
prepares  them  for  the  action  of  the  pepsin.  Eggs  are  digested  in  the 
same  manner  but  more  easily,  having  so  little  connective  tissue. 

Milk  is  first  acted  upon  by  rennin  which  sets  free  the  albumin 
contained  and  brings  out  the  casein  from  the  caseinogen,  in  the  form 
of  a  soft  coagulum  or  curd.  Pepsin  then  transforms  both  into 
peptone. 

Clinical  note, — The  curdled  milk  which  a  healthy  baby  regurgitates  is  a 
normal  substance;  the  rennin  has  acted  and  it  only  needs  the  pepsin  to 
complete  its  digestion. 

Vegetables  are  digested  in  the  stomach  only  so  far  as  the  protein 
which  they  contain  is  concerned;  sugar  and  starch  not  at  all. 

Fats  are  freed  from  their  connective  tissue  envelopes  and  float  as 
little  globules;  they  are  not  themselves  digested  here. 

Note. — The  mineral  salts  do  not  require  digestion.  They  are 
already  dissolved  in  the  water  for  the  purpose  of  entering  into 
combinations  in  the  tissues. 

When  any  portion  of  the  stomach  contents  is  sufficiently  pre- 
pared by  gastric  digestion,  the  pyloric  sphincter  relaxes  and  the 
rather  thick  yellowish  fluid  called  chyme  passes  through  it  into  the 
duodenum  and  thence  into  the  jejunum  and  ileum. 

Here  the  mechanical  process  is  a  continuation  of  the  peristaltic 
movement  of  the  stomach.  The  circular  fibers,  by  frequent  constric- 
tions of  the  tube,  divide  the  mass  and  force  it  along,  at  the  same  time 
preventing  a  too  rapid  passage.  The  longitudinal  fibers  assist,  by  a 
series  of  wave-like  contractions. 

The  chemical  process  consists  in  the  further  digestion  of  pro- 


FOODS   AND    DIGESTION.  I47 

teids,  sugars  and  starch;  also  the  digestion  of  fats.  Therefore  the 
intestinal  fluid  contains  several  ferments,  being  a  mixture  of  pan- 
creatic juice,  intestinal  juice  and  bile. 

The  intestinal  juice  completes  the  digestion  of  sugar  (and  possi- 
bly of  starch);  its  ferment  is  invertin. 

The  pancreatic  juice  acts  promptly  upon  starch  by  the  ferment 
amylopsin,  changing  it  to  sugar.  It  converts  protein  into  peptones  by 
the  ferment  trypsin, and  it  digests  fats  by  means  of  the  ferment  steap- 
sin,  which  emulsifies  them  into  a  white  fluid  called  chyle. 

The  bile  which  is  poured  into  the  duodenum  with  the  pancreatic 
fluid  is  an  aid  to  digestion  in  ways  not  perfectly  understood.  The 
intestinal  ferments  all  act  in  alkaline  fluids,  and  bile  is  alkaline. 
Experiments  and  observation  have  proved  that  the  presence  of  bile 
in  the  intestine  is  necessary  to  nutrition;  without  it  a  person  may 
eat  large  quantities  of  food  and  still  lose  weight  daily.  It  is  believed 
that  it  assists  the  absorption  of  fats  and  it  pretty  certainly  delays 
putrefactive  changes  in  the  intestines.  It  may  also  stimulate 
peristalsis. 

Clinical  notes, — The  reason  for  abstaining  from  ice-water  during  digestion 
is  that  the  various  ferments  cannot  do  their  work  in  a  temperature  much  less 
than  100°  F.  (If  people  will  eat  ice-cream  after  dinner  they  should  at  least 
take  it  slowly,  that  the  whole  process  of  digestion  be  not  too  long  delayed  by  the 
necessity  of  waiting  for  the  temperature  to  rise  again  to  100°. ) 

The  activity  of  the  salivary  glands  of  the  infant  does  not  begin 
under  three  or  four  months.  The  feeding  of  starchy  foods  should 
be  delayed  in  accordance  with  this  fact. 

The  passage  of  food  through  the  intestine  is  normally  slow,  and 
thus  it  is  fully  exposed  to  the  surfaces  of  the  circular  folds  of  the 
mucous  membrane.  By  the  absorption  of  digested  food  the  intes- 
tinal contents  are  diminished  in  quantity  and  changed  in  character, 
containing  less  water  and  approaching  a  firmer  consistency.  After 
passing  through  the  ileo-colic  sphincter  into  the  large  intestine  there 
is  little  but  waste  remaining,  undigested  food  forming  the  major 
portion.  This  collection  of  waste,  liquids,  coloring  matter  and 
undigested  food  is  called  feces.  The  coloring  matter  is  derived 
partly  from  bile,  partly  from  food  (it  may  be  modified  by  drugs; 
for  example,  iron  and  bismuth  giving  a  black  color  to  the  feces). 
(The  odor  is  due  to  sulphuretted  hydrogen  and  to  skatol — it  also  is 


148  AXATOMY  AD    PHYSIOLOGY   FOR   NURSES. 

modified  by  food.j  The  consistency  depends  upon  the  amounts  of 
water  and  mucus,  approaching  a  liquid  form  when  the  intestinal 
contents  are  hurried  through  the  tube  before  absorption  can  take 
place. 

Defecation  is  the  act  of  expelling  the  feces.  The  bowel  muscles 
contract  and  the  sphincter  ani  relaxes;  the  abdominal  muscles  assist 
by  compressing  the  organs  from  above.  The  dietary  which  con- 
tains the  largest  proportion  of  waste  material  will  leave  the  greatest 
quantity  of  feces  and  lead  to  more  frequent  defecation  than  one 
which  is  made  up  of  digestible  substances  only.  The  peristaltic 
action  of  the  bowel  is  made  more  effective  by  the  presence  of  a 
reasonable  amount  of  matter  to  be  acted  upon. 

Diarrhea  is  the  passing  of  frequent  loose  or  watery  stools.  It  occurs  when 
the  contents  of  the  small  intestine  are  hurried  along  too  rapidly  by  some  irritating 
substance  which  causes  excessive  peristalsis  and  a  leakage  of  the  watery  portion 
of  the  blood. 

Ccmstipation  is  caused  by  a  too  concentrated  diet  and  slow  peristalsis.  Since 
bile  is  a  natural  stimulant  to  the  muscles  of  the  bowel,  constipation  is  often 
associated  with  a  torpid  liver;  it  is  also  caused  by  lack  of  fluids  in  the  bowel. 
Therefore  this  is  one  reason  why  water  is  an  important  food. 

Absorption  of  Food. 

Accompanying  the  digestion  of  food  the  absorption  of  nutritive 
principles  takes  place. 

It  is  not  proven  that  food  is  absorbed  from  the  stomach;  as  fast  as 
it  is  digested  there,  it  is  discharged  as  chyme  into  the  small  intestine. 
After  it  is  acted  upon  by  intestinal  fluids  it  is  ready  to  be  absorbed. 
The  villi  (page  131)  are  the  absorbents  which  perform  this  function 
in  the  intestine.  The  epithelial  cells  with  which  they  are  covered 
take  up  and  transmit  the  new  substances  (formed  by  digestion)  into 
lymph  spaces  within  the  \illus,  from  which  they  go  either  into 
the  blood-vessels  or  lymph  capillaries  (page  149)  which  it  contains. 

Wafer  and  mineral  salts  (dissolved  in  the  water). — These  must  pass  into 
the  blood  capillaries,  thence  into  intestinnl  veins,  and  through  them  to  the 
portal  vein  (page  188).     By  this  they  are  taken  to  the  liver. 

Sugars,  dextrose  and  levulose  (which  result  from  the  digestion  of  carbo- 
hydrates). These  pass  by  the  same  route,  namely,  blood  capillaries  and 
veins  to  the  liver. 

Peptones  also  find  their  way  in  the  same  manner  to  the  portal  blood  and 
the  liver. 


ABSORPTION    OF    FOOD. 


149 


Thus  it  appears  that  all  proteins,  sugars,  water  and  salts  pass 
through  the  liver.  There,  water  and  salts  are  used  for  various 
combinations;  sugars  are  converted  into  glycogen  to  a  great  extent 
and  stored  for  future  use;  and  proteids  furnish  tissue  food  and 
materials  for  bile. 


Fig.  107 — Section  of  Ixtected  Small  Intestine  of  Cat.  a,  b.  Mucosa,  g.  Villi. 
i.  Their  absorbent  vessels,  h.  Simple  foUices.  c.  Muscularis  mucosa^.  7.  Submucosa. 
^,  e.  Circular  and  longitudinal  layers  of  muscle.  /.  Fibrous  coat.  All  the  dark  lines 
represent  blood-vessles  filled  with  the  injection  mass  (Piersol). 

Glycogen. — This  product  of  the  action  of  liver  cells  upon  carbohydrates  is 
stored  in  the  liver.  When  needed  it  is  returned  to  the  blood  (as  sugar  again) 
and  distributed  to  the  tissues,  notably  to  the  muscles.  Being  readily  oxidized  it 
favors  the  rapid  changes  in  muscles  which  result  in  motion.  Therefore,  it 
follows  that  sugar  and  starch  are  sources  of  muscle  energy. 

Urea. — This  is  another  substance  which  appears  as  a  result  of  the  activity 
of  the  liver  cell.  It  represents  the  final  form  of  waste  derived  from  the  metab- 
olism of  proteid  substances.  It  is  a  very  poisonous  waste  and  is  eliminated  from 
the  blood  by  the  kidneys. 

Having  yielded  materials  for  these  functions,  the  remaining  food 
substances  are  carried  away  from  the  liver  by  hepatic  veins  and  finally 


ISO 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


into  the  general  circulation,  to  be  distributed  to  the  tissues  of  the 
body. 

There  remain  the  fats:  These,  being  transferred  by  the  epithelial 
cells  to  the  lymph-spaces,  take  the  other  route,  in  the  form  of  an 
emulsion  known  as  chyle.  They  pass  into  the  lymph  capillaries  of 
the  intestine  (so-called  lacteals),  which  open  into  the  lymph  vessels 
in  the  submucous  coat.  By  these  vessels  the  chyle  finally  reaches 
the  thoracic  duct  and  is  carried  into  the  general  circulation  to  be 
distributed  to  the  tissues  of  the  body  (Fig.  io8). 

Another  view  is  held  concerning  the  digestion  and  absorption  of  fats — that 
the  results  of  digestion  are  soaps  and  glycerin,  which  are  easily  absorbed. 
However  they  may  be  absorbed  by  the  epithelium,  they  are  in  the  form  of  an 
emulsion  in  the  lacteals. 


Lacteals 


Blood  vessels 


Fig.  108. — Loop  of  Small  Intestine  with  Lacteals  (Morris). 


In  the  tissues. — The  solution  of  nutritive  substances,  having  been 
carried  by  the  blood-vessels  to  the  minutest  channels  in  the  body, 
passes  into  the  tissue  spaces  as  Ijmiph,  which  bathes  the  cells 
themselves  so  that  they  may  receive  the  material  necessary  for 
their  action  and  upbuilding. 

Different  tissues  appropriate  their  different  foods,  and  each  gives 
back  the  products  of  its  own  activities  as  tissue  wastes,  which  in  turn 
enter  the  blood  to  be  carried  to  tissues  which  can  make  another  use  of 
them,  or  to  organs  which  can  dispose  of  them  as  excretions. 


FOODS   AND    DIGESTION.  I51 

Digestion. — Is  the  process  of  so  changing  the  food  that  it  may  be 
absorbed. 

Absorption. — Is  the  process  of  taking  up  certain  substances  and 
conveying  them  to  the  blood. 

Circulation. — Is  the  process  of  carrying  the  blood  and  other 
substances  to  every  part  of  the  body. 

Assimilation. — Is  the  process  which  goes  on  in  the  tissue  cells 
whereby  they  make  use  of  the  food  which  is  conveyed  to  them. 

We  have  now  to  study  the  organs  which  distribute  the  products 
of  digestion,  and  the  composition  of  the  food-bearing  fluids — blood 
and  lymph.  Assimilation  is  nature's  own  secret,  not  yet  revealed  to 
the  mind  of  man. 


CHAPTER  X. 
THE  BLOOD  AND  THE  CIRCULATORY  SYSTEM. 

THE  BLOOD. 

The  blood  is  the  most  important  fluid  in  the  body.  It  not  only 
carries  food  to  every  part,  but  bears  waste  matters  to  those  organs 
which  can  dispose  of  them  in  the  form  of  excretions.  It  consists  of 
a  clear  yellowish  fluid  called  plasma  and  small  round  cells  (invisible 
to  the  naked  eye)  called  corpuscles  (little  bodies),  which  float  in 
the  plasma. 

The  corpuscles  are  of  two  sorts,  red  and  white. 

It  is  convenient  to  follow  the  usage  common  in  clinical  work  and  speak  of 
them  as  red  and  white  cells.  A  third,  smaller,  colorless  cell  exists  in  blood,  named 
a  hlood  plate. 


Fig.  109. — Corpuscles  of  Blood,  as  seen  under  the  Microscope. 
Four  white  ones  are  shown.     The  red  ones  have  a  tendency  to  form  rows  (Funke 
and  Brubaker). 

The  temperature  of  the  blood  is  about  100°  F. 

The  reaction  is  alkaline. 

The  red  cells  {erythrocytes)  are  non-nucleated,  flexible  and 
elastic.  They  are  very  numerous,  numbering  4,000,000  to  4,500,000 
in  a  cubic  centimeter.     They  measure  about  2^-5W  of  an  inch  in 

152 


THE    BLOOD. 


153 


diameter,  and  their  shape  has  been  usually  described  as  that  of  a 
flattened  sphere  (Fig.  109). 

Note. — The  illustration  presents  the  appearance  under  the  microscope 
of  blood  which  has  been  removed  for  a  time  from  the  vessels  and  cooled. 
Careful  studies  under  other  conditions,  indicate  that  the  living  cells  are 
slightly  hell-shaped. 

.T)^^^j^j^^,  cells  are  composed  largely  of  hemoglobin.  This  itself  is 
amb^^  j:oJ,Qred,  but  when  a  great  number  of  cells  are  together  as  in  a 
drop  pf  blood,  it  gives  the  red  hue  to  the  fluid. 

Hemoglobin  is  a  proteid  substance  whose  most  important 
propertY^.^i^  its  power  to  combine  with  oxygen  and  to  give  it  up.  It 
contai^^a  minute  quantity  of  iron  in  combination  (hematin)  which 
is  neC|^^sa-ry  to  life  processes. 

The  origin  of  the  red  cells  is  in  the  red  marrow  of  cancellous  bone. 

The  white  cells  or  leucocytes  are  of  different  sizes  (the  largest  be- 
ing about  Winr  of  an  inch  in  diameter).  They  move  more  slowly 
in  the  plasma  and  are  far  less  numerous,  numbering  only  about 
7500  in  a  centimeter. 


Fig.  1 10 — \\'hite  Corpuscles  Penetrating  Capillary  Walls 
(Landois  and  Stirling). 


They  are  nucleated,  flexible  and  elastic.  Their  shape  is  spher. 
ical  (often  irregular),  and  they  consist  of  a  transparent  material 
containing  one  or  several  nuclei  and  many  fine  granules  (of  proteid 
substances). 

The  white  cells  frequently  change  their  shapes  by  means  of 
ameboid  movements,  that  is,  like  the  ameba,  they  thrust  out  portions 
of  their  substance  and  draw  them  back.     They  can  send  out  little 


154  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

prolongations  and  draw  floating  particles  to  themselves,  or  they  can 
wrap  themselves  around  foreign  substances. 

They  possess  also  the  power  of  slipping  (squeezing)  through  the 
walls  of  capillary  vessels.     This  is  called  diapedesis  (Fig.  no). 

Of  the  five  distinct  varieties  of  leucocytes  the  percentage  of  polymorpho- 
nuclear cells  {nuclei  of  many  shapes)  is  the  largest. 

The  polymorphonuclear  cells  (oftenest  called  polynuclear)  and 
the  lymphocytes  are  called  phagocytes,  because  they  destroy  bacteria 
by  absorbing  and  digesting  them.  This  process  is  caXltd  phagocyto- 
sis (to  be  referred  to  later  on).  o:'^--' 

The  origin  of  the  white  cells  is  from  two  sources;  the  lymphocytes 
originate  in  lymph  glands  "and  other  lymphoid  tissues;  the  poly- 
nuclear leucocytes  and  others  are  developed  from  cells  in  the  marrow 
of  long  bones. 

The  plasma  is  a  thin  watery  saline  fluid  in  which  the  corpuscles 
float.  It  contains  both  nutritive  and  waste  matters  in  solution,  and 
also  certain  elements  from  which  fibrin  is  derived.  The  fibrin  is 
essential  to  the  production  of  a  blood-clot,  without  which  hemorrhage 
would  never  cease  of  its  own  accord. 

The  substances  dissolved  in  the  watery  portion  of  the  plasma  are: 


Serum-albumin 
Proteids.  ...    \  Fibrinogen 


Nutritive  (derived  from  food) { 


Paraglobulin 


Sugars 
Fats 


Waste  products    (derived    from    tissue  .  j  Urea 

,  .  Extractives    Wt  •        -j     ^ 

changes).  [  Uric  acid,  etc. 

[  Sodium 

Mineral  salts.     Chiefly  salts  of     \  Potassium 

[  Calcium 

The  serum-albumin  is  the  great  tissue  builder.  The  fibrinogen  is 
the  fibrin  maker  (paraglobulin  may  assist  in  this;  its  use  is  not  fully 
known) . 

Sugars  and  fats  are  tissue  foods. 

Mineral  salts  preserve  the  necessary  alkalinity  of  the  blood  and 
assist  in  the  formation  of  certain  tissues  (as  bone) .  Sodium  chloride 
(common  salt)  is  the  most  abundant  (and  to  this  is  due  the  salinity 
of  the  blood).' 

^  A  "normal  saline  solution"  contains  salt  in  the  proportion  found  in  blood. 


PROCESS    OF    COAGULATION, 


155 


Coagulation  of  Blood. 

Blood  which  is  exposed  to  the  air  at  the  usual  temperature  is 
seen  to  separate  into  distinct  portions — a  red,  jelly-like  mass  and  a 
transparent  straw-colored  layer  which  is  thinner.  The  dark  mass 
is  the  coagulum,  consisting  of  fibrin  with  corpuscles  entangled  in  it. 
The  straw-colored  layer  above  it  is  serum,  which  is  plasma  bereft 
of  its  fibrin  and  corpuscles  (Fig.  iii).  This  same  process  may 
occur  at  the  mouth  of  a  blood-vessel  which  has  been  cut  or  ruptured, 
if  the  stream  be  not  too  forcible,  and  it  is  nature's  way  of  stopping 
the  flow. 


I.  2.  3. 

Fig.  III. — Diagram  to  Illustrate  the  Process  of  Coagulation,  i.  Fresh 
blood,  plasma,  and  corpuscles.  2.  Coagulating  blood  (birth  of  fibrin).  3.  Coagulated 
blood  (clot  and  serum)  (Waller). 

A  clot  of  fibrin  may  be  formed  within  a  blood-vessel  if  the  interior  surface  is 
rough  and  the  stream  slow;  this  does  not  occur  in  health. 

The  formation  of  fibrin  from  fibrinogen  is  a  process  confined  to  the  plasma; 
the  corpuscles  remain  unchanged  and  are  simply  incidental  constituents  of  the 
coagulum  or  clot.  Fibrin  itself  is  colorless,  as  may  be  seen  when  it  is  whipped 
out  from  fresh  blood  by  twigs  or  rods. 

The  coagulation  time  of  blood  is  of  some  importance,  as  it  varies 
in  health  or  disease;  for  example,  it  is  delayed  in  certain  inflammatory 
conditions. 


Diagram  of  Change  from  Fluid  to  Coagulated  Blood. 


Corpuscles,  they  unite   with  \ 


Fluid  blood 


Plasma,  consists  of 


j  Fibrin 


to  form  Coagulum 


I  Coagulated 
1       blood 


\  Serum  remains  Serum 

Opsonins  and  ihe  opsonic  index. — It  is  believed  that  the  phago- 
cytic action  of  white  cells  is  regulated  by  the  presence  in  'the  blood 
of  chemical  substances  (still  undescribcd)  called  opsonins,  by  which 
invading  bacteria  arc  prepared  for  absorption  and  digestion  by  the 
phagocytes.     The  measure  of  the  power  thus  residing  in  the  blood 


156  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

is  expressed  as  the  opsonic  index.  The  opsonic  index  is  high  or  low, 
according  to  the  number  of  bacteria  which  the  cells  may  be  able  to 
dispose  of. 

There  is  some  reason  for  thinking  that  a  special  opsonin  exists 
for  each  kind  of  bacterium. 

THE  CIRCULATORY  SYSTEM. 

This  system  includes  the  heart  and  blood-vessels  or  arteries, 
capillaries  and  veins.     They  are  the  organs  which  contain  the  blood. 

The  heart  is  a  pump.  The  arteries  are  elastic  tubes  which  receive 
the  blood  directly  from  the  heart.  The  capillaries  are  small  vessels 
into  which  the  arteries  lead,  and  the  veins  carry  the  blood  from  the 
capillaries  back  to  the  heart. 

Arteries. — ^Vessels  which  convey  the  blood  away  from  the  heart. 
They  are  flexible  tubes  whose  walls  consist  of  three  layers  or  coats — 
external,  middle,  and  internal  (or  tunica  adventitia,  tunica  media,  and 
tunica  intima).  The  external  coat  is  composed  of  fibrous  tissue  to 
which  the  strength  and  toughness  of  the  vessel  is  due;  the  middle  is 
composed  of  elastic  tissue  and  unstriped  muscle  fibers,  giving  to 
arteries  their  yielding  and  contractile  character;  the  internal  is  thin 
and  smooth  and  is  a  continuation  of  the  lining  of  the  heart.  (It  is 
sometimes  called  the  serous  coat.)  Arteries  of  medium  size  have 
most  muscle  tissue,  while  the  larger  ones  have  most  elastic  tissue.  It 
is  owing  to  their  elasticity  that  arteries  remain  open  when  they  are 
empty  or  cut  across. 

Note. — The  internal  coat  is  the  only  one  which  is  continuous  throughout  the 
entire  circulatory  system. 

Surgical  note. — When  a  ligature  is  tied  tightly  around  an  artery  the  middle 
coat  may  be  felt  to  break  down  under  the  cord,  while  the  external  one  remains 
whole,  owing  to  its  toughness. 

The  arteries  give  off  branches  which  divide  and  subdivide  until 
the  smallest  ones  can  be  seen  only  with  the  microscope — they  are 
called  arterioles.  The  arterioles  lead  to  the  vessels  which  are 
smallest  of  all — the  capillaries. 

Capillaries. — ^Vessels  which  receive  blood  from  the  arteries  and 
carry  it  to  the  veins.  They  exist  in  nearly  every  part  of  the  body, 
except  cartilages,  hair,  nails,  cuticle,  and  the  cornea  of  the  eye. 
Their  walls  have  only  the  internal  coat,  a  single  layer  of  cells— 
endothelium.     It  is  through  these  thin  walls  that  the  work  of  exchange 


THE   HEART. 


157 


is  performed  between  the  blood  and  the  various  tissues  of  the  body, 
nutritive  material  being  taken  from  the  blood  and  certain  waste 
substances  being  returned  to  it.  To  provide  vessels  for  this  ex- 
change is  the  function  of  .the  capillaries. 

Their  average  diameter  is  ^iMjg-  of  an  inch — just  enough  to  permit  the  easy- 
passage  of  the  corpuscles. 

Veins. — The  vessels  which  gather  the  blood  from  the  capillaries 
and  carry  it  to  the  heart;  they  are  formed  by  the  uniting  of  capillaries. 

They  are  at  first  very  small  (called  venules  or  venous  radicles)  but  constantly 
grow  larger  by  uniting  with  each  other,  although  they  often  branch  and  reunite. 

Veins,  like  arteries,  have  three  coats,  but  their  middle  coat  is 
neither  so  elastic  nor  so  muscular,  so  that  they  are 
softer,  and  when  empty  or  cut,  they  collapse. 
The  inner  coat  of  the  veins  presents,  at  intervals, 
semilunar  folds,  making  pockets  called  valves, 
which  allow  the  blood  to  flow  toward  the  heart, 
but  prevent  it  from  setting  backward  freely.  (If 
the  veins  are  very  well  filled  the  location  of  the 
valves  may  be  recognized  by  an  appearance  of 
puffing  out  at  those  points  where  they  exist.) 
(Fig.  112.) 

Blood-vessels  possess  nerves^  which,  by  con- 
trolling the  muscular  coats,  regulate  the  amount 
of  blood  flowing  through  them  at  a  given  time  to 
the  structures  which  they  supply.  (An  organ  at 
work  needs  more  blood  than  an  organ  at  rest.) 

They  also  possess  tiny  blood-vessels  in  their  walls,  the 


vasa  vasorum. 


Fig.  112. — A  Vein 
Laid  Open  to  Show 
Valves. 


All  blood-vessels  have  sheaths  of  connective  tissue.  In  the  case 
of  the  larger  ones  these  are  quite  strong  and  sometimes  inclose  a 
vein,  an  artery,  and  a  nerve  together. 


The  Heart. 

The  heart  is  a  hollow  muscular  organ  through  which  the  blood 
passes,  placed  behind  the  sternum  and  just  above  the  central  tendon 
of  the  diaphragm. 

Note. — The  muscle  tissue  of  the  heart  is  called  the  myocardium. 
'  Vaso-motor  nerves. 


158 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


It  is  shaped  like  a  cone,  about  five  inches  long  and  three  and 
one-half  inches  wide,  with  the  base  turned  upward  toward  the  right 
shoulder  and  the  apex  pointing  downward  toward  the  left  side. 
It  is  composed  of  several  layers  of  muscle  fibers  which  are  peculiar, 
being  involuntary  and  at  the  same  time  striped. 

The  cavity  of  the  heart  is  divided  by  a  septum  into  right  and  left 
portions,  and  as  it  lies  in  the  body  the  right  heart  is  nearly  in  front 
of  the  left.  Each  side  consists  of  two  chambers,  an  auricle  (atrium) 
and  a  ventricle  (ventriculum)  (Fig.  114). 


Posterior   branch   of       // 
right  coronary  ar 
tery 

Auricular  appendage 
Right  coronary  artery 

Preventricular    branch 
Right  marginal  branch 


Posterior  interventicu- 
lar  branch  of  right 
coronary  artery 


Transverse   branch    of 
right  coronary  artery 


Left  coronary  artery 


Anterior  interventricu- 
lar branch    of   left 
coronary  artery 


Left  marginal  branch 


Fig.  113. — Anterior  Surface  of  Heart  (Morris). 
The  coronar}'  arteries  supply  the  substance  of  the  heart. 


The  auricles  receive  blood  and  pass  it  into  the  ventricles. 
Their  walls  are  thin  and  flabby.  The  right  auricle,  or  atrium, 
presents  two  large  openings  for  the  entrance  of  veins,  and  one  for 
communication  with  the  right  ventricle.  The  veins  are  the  superior 
vena  cava  from  the  head  and  upper  extremities;  the  inferior  vena 
cava  from  the  trunk  and  lower  extremities.  It  also  has  a  transverse 
fold  on  the  posterior  wall  called  the  Eustachian  valve  or  valve  of  the 
inferior  vena  cava,  and  a  round  depression  on  the  septum  between  the 
two  auricles  (atria),  called  the  oval  fossa  {fossa  ovalis).     The  left 


VENTRICLES  OF  THE  HEART. 


159 


auricle  presents  two  large  openings  and  several  small  ones  for  veins, 
and  communicates  with  the  left  ventricle. 

The  ventricles  expel  blood  from  the  heart.  They  include  the 
apex  of  the  heart  and  their  walls  are  thick  and  strong,  the  left  one 
being  the  thicker  and  larger  of  the  two.     Certain  muscle  libers  in 


Fig.  114. — IxTERiOR  of  Left  Heart.  (Observe  the  difference  in  thickness  of 
the  walls  in  auricle  and  ventricle.)      (Allen  Thomson  in  Bruhaker.) 

I,  L.  atrium  or  auricle;  2,  division  between  it  and  ventricle;  3,  wall  of  left  ventricle; 
4,  a  band  of  muscle  fibers  severed;  5,  other  muscle  bands;  6,  a  leaflet  of  mitral  valve, 
with  tendinous  cords;  7,  aorta  (a  large  artery)  laid  open  to  show  semilunar  valves;  8, 
pulmonary  artery  (semilunar  valves  closed) ;  q,  arc  h  of  aorta. 


the  ventricles  pass  downward  to  wind  around  the  apex  of  the  heart 
and  then  turn  upward;  others  are  transverse,  still  others  oblique; 
the  arrangement  causing  the  heart  to  harden  in  contraction,  with  a 
twisting  motion  from  right  to  left  and  a  forcible  pressure  against  the 
chest  wall.  This  is  felt  in  the  fifth  interspace,  at  the  left  of  the 
sternum  and  is  called  the  cardiac  impulse. 


i6o 


ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 


The  muscle  hand  of  His  is  a  name  given  to  a  bundle  of  muscle 
fibers  which  connects  the  auricles  and  ventricles;  the  contraction 
impulse  is  believed  to  travel  from  auricle  to  ventricle  by  these  fibers. 

The  interior  of  the  ventricles  is  marked  with  a  number  of  ridges 
or  bands  of  muscle  fibers  (the  traheculcB  carnece),  and  certain  of  these 
are  attached  by  tendinous  cords  to  the  valves  of  the  heart.  Each 
ventricle  opens  into  a  large  artery,  which  conveys  the  blood  away 
— the  pulmonary  artery  from  the  right  ventricle,  the  aorta  from  the 
left. 

Note. — In  the  new  nomenclature  the  name  "atrium,"  or  forechamber,  is 
given  to  the  main  part  of  the  auricle,  and  the  word  auricle  applies  to  the  auricular 
appendage  alone;  the  opening  from  auricle  to  ventricle  is  called  ostium  venosum. 

Endocardium. — The  lining  of  the  heart.  It  is  thin  and  firm, 
resembling  serous  membrane  in  appearance,  and  is  continuous  with 
the  lining  of  the  arteries  and  veins,  thus  making  a  perfectly  smooth 
surface  throughout,  for  the  current  of  blood. 


The  Valves  of  the  Heart, 

The  valves  of  the  heart  are  formed  by  folds  of  endocardium 
strengthened  by  fibrous  tissue  and  placed  at  certain  orifices  of  the 

different  chambers — two  in 
the  right  heart  and  two  in 
the  left.  The  opening  be- 
tween the  right  auricle  and 
ventricle  (right  ostium  veno- 
sum) is  guarded  by  the  tri- 
cuspid valve,  which  is  com- 
posed of  three  leaflets.  It 
allows  the  blood  to  flow 
down  into  the  ventricle  but 
prevents  it  from  flowing 
back.  The  opening  between 
the  left  auricle  and  ventricle 
(left  ostium  venosum)  is 
guarded  by  the  bicuspid  (or 
mitral)  valve,  composed  of 
two  leaflets,  allowing  the  blood  to  flow  down  into  the  ventricle  but 
not  to  return.     (Both  the  tricuspid  and  mitral  valves  are  connected 


Fig.  115. — ^Valves  of  the  Heart. 
1.  Right  auriculo-ventricular  orifice,  dosed 
by  the  tricuspid  valve.  2.  Fibrinous  ring.  3. 
Left  auriculo-ventricular  orifice,  closed  by  the 
mitral  valve.  4.  Fibrous  ring.  5.  Aortic 
orifice  and  valves.  6.  Pulmonic  orifice  and 
valves.  7,  8,  9.  Muscular  fibers  (auricles  re- 
moved) (Bonamy  and  Beau.) 


VALVES    OF    THE    HEART.  l6l 

to  certain  muscle  bands  of  the  ventricles  by  tendinous  cords  which 
control  the  motion  of  the  leaflets,  preventing  them  from  flying  up- 
ward too  far  when  the  ventricles  contract.)      (Fig.  114.) 

The  opening  from  the  right  ventricle  into  the  artery  which  leaves 
it  {pulmonary  artery),  is  guarded  by  three  semiluna  rvalves,  which  are 
half-moon  shaped  pockets  called  the  pulmonary  valves.  Likewise 
the  opening  from  the  left  ventricle  into  its  artery  {aorta)  is  guarded 
by  three  semilunar  valves  called  the  aortic  valves  (Fig.  115). 

The  semilunar  valves  allow  the  blood  to  flow  in  one  direction  only 
— that  is,  away  from  the  heart. 


Fig.  116.     (Diagram.) 
The  right  auricle  receiving  blood  and  passing  it  through  tricuspid  valve  into  right  ven- 
tricle, which  is  dilated  {semilunar  valves  closed)  (Dalton  in  Brubaker). 


Functions  of  the  Chambers  of  the  Heart. 

The  auricles,  having  received  blood  from  the  veins  opening  into 
them  (the  right — blood  from  entire  body;  left — from  lungs  alone) 
gently  contract  together  to  send  it  down  into  the  ventricles;  quickly 
the  ventricles  contract,  forcibly  and  together,  expelling  blood  into 
the  two  large  arteries — the  pulmonary  carrying  it  to  the  lungs,  the 
aorta  to  all  parts  of  the  body.  This  process  is  the  systole  of  the 
heart;  it  occupies  about  eight- tenths  of  a  second,  perhaps  a  trifle 
more.  Then  comes  the  resting-timc  when  the  heart  is  dilating  and 
filling  again,  called  the  diastole  of  the  heart. 


l62  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

During  the  systole  of  the  auricles,  the  tricuspid  and  mitral  valves 
are  open  and  the  semilunar  valves  are  closed.  During  systole  of  the 
ventricles  the  tricuspid  and  mitral  valves  close,  and  the  semilunar 
valves  are  open  (Figs.  ii6,  117). 

The  thickness  of  the  ventricle  wall  is  explained  by  the  need  for 
sending  blood  to  a  distance,  the  greater  thickness  of  the  left  being 
made  necessary  by  the  far  greater  work  required  of  it. 

The  systole  of  the  ventricles  corresponds  to  the  "heart-beat" 
It  occurs  at  perfectly  regular  intervals  in  health,  the  rate  being  from 


Fig.  117. 

The  right  ventricle  filled,  contracts  and  expels  blood  through  semilunar  valves  {tricuspid 

valve  closed)  (Dalton  in  Brubaker). 

sixty  to  seventy  per  minute  in  men,  and  from  seventy  to  eighty  in 
women.  The  heart's  action  is  more  rapid  in  the  upright  position 
than  in  sitting  or  lying,  and  is  increased  by  any  exercise,  however 
gentle.  Excitement  or  emotion  will  quicken  it  at  once,  and  it  is 
always  fastei:  in  children,  being  about  one  hundred  and  forty  in 
the  newly  born  and  reaching  an  average  rate  of  ninety  to  one 
hundred  at  the  age  of  three  years;  ninety  in  youth,  seventy  in 
adults,  and  eighty  in  old  age. 

The  Pulse. — The  effect  of  the  heart-beat  upon  the  current  of  the 
blood  may  be  felt  in  the  arteries,  which  are  distended  for  an 
instant  by  the  blood  forced  into  them  as  the  ventricles  contract. 


SOUNDS  OF  THE  HEART. 


163 


This  gives  the  effect  of  a  beating  in  the  arteries,  which  is  called  the 
pulse.  The  pulse-rate  corresponds  with  the  heart-beat;  therefore, 
the  rate  and  force  of  the  heart's  action  are  judged  by  means  of  the 
pulse. 

The  Heart  Sounds. 

The  action  of  the  heart  causes  certain  sounds,  named  the  first 
and  secand.  The  first  accompanies  the  sudden  closure  of  the  tri- 
cuspid and  mitral  valves,  as  the  ventricles  contract.     It  is  the  systolic 


UPPER   ATTACHMENT 
OF    PERICARDIUM   ' 


3RANCHES    OF    PUL 

MONARY    ARTERY 

AORTAr. 


BRANCHES    OF 

IPULMONARY   ARTERY 

-PULMONARY 

ARTERY 


DIAPHRAGM  PERICARDIUM 


ATTACHMENT    OF 


DIAPHRAGM 


Fig.  118.- 


RIGHT 
VENTRICLE        PERICARDIUM 
TO  DIAPHRAGM 

-The  heart  in  situ.     The  pericardium  has  been  cut  open  in  front, 
and  reflected  (Testut). 


sound — caused  by  the  systole  of  the  ventricles.  The  second  ac- 
companies the  sudden  closure  of  the  semilunar  valves.  It  is  the 
diastolic  sound,  occurring  with  the  diastole  of  the  ventricles. 

The  first  or  systolic  sound  is  the  louder  and  larger,  being  due  to 
the  contracting  of  muscle  fibers  as  well  as  to  closure  of  valves.  The 
second,  diastolic  sound  is  short  and  sharp,  due  to  valve  closure  only. 
The  two  sounds  are  compared  to  the  spoken  words — luhh  dupp. 


l64  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

When  the  blood  is  forced  into  the  elastic  arteries  by  a  contraction  or  beating 
of  the  heart  it  stretches  them.  When  the  contraction  is  ended,  the  wall  of  the 
artery  recoils  and  there  is  a  setting  back  of  the  blood  for  an  instant  toward  the 
heart,  but  it  is  stopped  by  the  closing  semilunar  valves,  which  thus  make  the 
second  sound. 

Clinical  note. — If  the  valves  of  the  heart  are  rough,  the  sounds  are  changed 
by  a  "murmur."  If  they  cannot  close  perfectly,  a  portion  of  the  blood  will 
flow  backward  instead  of  going  forward,  and  this  is  regurgitation.  This,  also, 
changes  the  sound  of  a  valve  and  causes  a  murmur. 

The  pericardium  (Fig.  ii8). — A  loose  serous  sac  enclosing 
the  heart.  The  layer  which  closely  covers  the  heart,  or  the  visceral 
layer,  is  the  epicardium.  It  covers  the  aorta  and  pulmonary  arteries 
for  about  one  inch,  then  leaves  them  to  become  the  parietal  layer  or 
lining  of  the  fibrous  sac  w^hich  encloses  the  whole,  and  which  is 
closely  attached  to  the  diaphragm  below  and  the  great  vessels  above. 
A  small  quantity  of  pericardial  fluid  prevents  friction  between  the 
surfaces,  as  the  smoothly  covered  heart  beats  in  the  smoothly  lined 
cavity;  this  increases  in  inflammation  of  the  pericardium,  or  peri- 
carditis, and  it  is  sometimes  necessary  to  remove  it  by  tapping. 

Review. — ^Principal  Points  of  Interest  in  the  Heart. 

Right  Auricle. 

Openings  of  two  large  veins  bringing  blood  from  the  body. 

Opening  of  coronary  sinus  bringing  blood  from  the  heart  itself. 

Oval  fossa  and  annulus  ovalis. 

Eustachian  valve  (or  valve  of  inferior  vena  cava). 

R.  Ostium  venosum  with  tricusped  valve. 

Right  Ventricle. 

R.  Ostium  venosum  and  tricuspid  valve. 
Opening  for  pulmonary  artery,  and  pulmonary  valves. 
Trabeculas  carneae  (fleshy  bands),  and  the  tendinous  cords  con- 
jiecting  them  with  tricuspid  valve. 

Left  Auricle. 

Openings  of  three  or  four  pulmonary  veins. 

L.  Ostium  venosum  with  bicuspid  (or  mitral)  valve. 


PULMONARY    CIRCULATION. 


165 


Left  Ventricle. 
L.  Ostium  venosum  and  bicuspid  valve. 
Opening  for  aorta  and  aortic  valves. 

Trabeculae  carneae  and  the  tendinous  cords  connecting  them 
with  the  bicuspid  valve. 

The  Course  of  the  Blood  Through  the  Heart. 

Resume. — The  blood  enters  the  right  auricle,  passes  down  into  the 
right  ventricle,  and  out  through  the  pulmonary  artery  to  the  lungs; 
it  returns  by  the  pulmonary  veins  to  the  left  auricle,  passes  down 


Left  carotid  artery    ^ 


Left  suhclav-ia      . 
artLTv 


Pulmonary  artery 

Pulmonary  veins 
from  left  lung 

Left  auricle 


Coronary  vessels 


—  Anonyma 


Superior  vena  cava 


Pulmonary  veins 
from  right  lung 


—     Right  auricle 


II     j\ 

'jT-   Inferior  vena  cava 


Coronary  artery 


Fig.  iiq. — Posterior  Surface  of  Heart. 
Pulmonary  veins  bringing  pure  blood  to  left  auricle  (Morris'  Anatomy). 

into  the  left  ventricle,  and  out  through  the  aorta  to  every  part  of  the 
body,  from  which  it  is  returned  by  two  large  veins  to  the  right 
auricle  again. 

The  course  from  the  right  ventricle  through  the  lungs  and  back  to 
the  left  auricle  is  called  the  pulmonary  circulation  (Fig.  119). 


l66  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

The  course  from  the  left  ventricle  through  the  entire  body  or 
"system"  and  back  to  the  right  auricle  is  called  the  systemic 
circulation  (Fig.  120). 

Important  notes. — ^Pure  blood  is  carried  from  the  heart  through  the  systemic 
arteries  to  all  tissues  in  the  body  to  nourish  them.  This  blood  is  called 
arterial  blood;  it  is  bright  red  in  color.  The  terms  piire  blood  and  arterial  blood 
are  used  to  signify  one  and  the  same  thing. 

Impure  blood  from  the  tissues  of  the  body  is  returned  to  the  heart  by  the 
systemic  veins.  It  is  called  venous  blood;  it  is  purple-red  or  blue  in  color  and 
contains  waste  matters.  The  terms  impure  blood  and  venous  blood  are  used  to 
signify  one  and  the  same  thing. 

The  venous  blood  from  the  body  is  poured  into  the  right  side  of  the  heart, 
from  which  the  pulmonary  artery  conveys  it  to  the  lungs.  Consequently  the  pul- 
monary artery  is  unlike  others,  because  it  carries  venous  blood  from  the  heart; 
and  the  pulmonary  veins  are  peculiar  because  they  carry  arterial  blood  to  the 
heart. 


CHAPTER  XI. 
THE  CIRCULATION  AND  FUNCTIONS  OF  BLOOD. 

THE  PULMONARY  CIRCULATIOX. 

This  is  the  circulation  of  the  blood  through  the  lungs,  that  it 
may  become  aerated  or  purified. 

The  puknonary  artery  leaves  the  right  ventricle,  carrying 
impure  blood,  and  soon  divides  into  two  branches,  the  right  and 
left  (one  for  each  lung),  which  break  up  into  a  capillary  network 
around  the  air  cells.  From  this  network  veins  arise  which,  by 
uniting,  form  two  from  each  lung,  making  the  four  pulmonary 
veins  carrying  purified  blood  to  the  left  side  of  the  heart.  They 
enter  the  left  atrium. 

THE  SYSTEMIC  CIRCULATION. 

This  is  the  circulation  of  the  blood  through  the  entire  body  or 
"system,"  that  it  may  nourish  the  tissues  and  organs  (Fig.  120). 

Arteries  of  the  Systemic  Circulation.^ 

The  aorta,  having  received  the  pure  blood  from  the  lungs, 
leaves  the  left  ventricle,  arches  over  the  root  of  the  left  lung  to  the 
left  side  of  the  fourth  thoracic  vertebra,  then  (gradually  coming  to 
the  front  of  the  spinal  column)  passes  down  through  the  diaphragm, 
and  ends  by  dividing  at  the  fourth  lumbar  vertebra,  (a  little  below 
the  level  of  the  umbilicus).  Thus  it  consists  of  three  portions:  the 
arch,  the  thoracic  aorta,  and  the  abdominal  aorta  (Fig.  121). 

The  arch  of  the  aorta  extends  from  the  heart  to  the  body 
(lower  border)  of  the  fourth  thoracic  vertebra.  It  reaches 
almost  as  high  as  the  sternal  (or  jugular)  notch. 

It  may  be  felt  in  thin  persons  by  pressing  the  finger  tip  down  behind  the  bone. 

'  The  names  of  all  of  the  arteries  .re  given  in  tabular  form  on  page  312.  Only  the 
principal  ones  are  here  described. 

167 


1 68 


SYSTEMIC   CIRCULATION. 


Fig.  1 20. — Scheme  of  Systemic  Circulation. 
Arteries  colored  red;  veins  blue. 


THE   AORTA. 


169 


RIGHT    COMMON- 
CAROTID 

Jugular  vein 


LEFT  COMMON 
CAROTID 

Vagus  nerve 


Thoracic  duct 
L.  V.  anonyma 

LEFT  SUBCLA- 
\IAN  ARTERY 


^p^  !  Nerves  and 

'  '        veins 


Fig.  121. — The  Aorta,  showing  the  Three  Portions  (Morris). 


lyo 


ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 


Branches  of  the  arch  in  their  order: 

Two  coronary  (right  and  left) to  heart  muscle  (Fig.  113). 

Right    subclavian    to  right 


One  anonyma,  ij  inches  long.  .  .  < 


upper  extremity. 
Right    common  carotid    to 
[      right  head  and  neck. 

One  left  common  carotid to  left  head  and  neck. 

One  left  subclavian to  left  upper  extremity. 


Phrenic  nerve 

Subclavian  artery 

Subclavian  vein 


Anterior  intercostal 
branch 


Branch  of  mammary 


Common  carotid 

Internal  jugular  vein 
Subclavian  vein 
Scalenus  anterior  muscle 

—  Sternum 


I  Perforating  branches 
/_j     \        (supplying  mam- 
mary gland) 


Superior    epigastric,  running 
down  from  internal  mammary 


Inferior  epigastric,  running 
up  from  external  iliac 


Fig.  122. — Showing  Subclavian  Artery  and  two  of  its  Branches 
(Thyroid  axis  and  internal  mammaiy)      (Morris). 

The  Principal  Arteries  of  the  Upper  Extremity. 

The  subclavian  artery  (Fig.  122)  passes  out  over  the  first  rib 
and  under  the  clavicula  (therefore  subclavian)  to  the  axilla,  or 
armpit.     The  brachial  plexus  lies  above  it  in  the  neck,  and  the 


THE  AXILLARY  ARTERY. 


171 


subcla\'ian  vein  is  in  front  of  it.  The  right  subcla\dan  is  a  branch 
of  the  anonyma.  Both  subclavians  end  at  the  lower  border  of  the 
first  rib. 

Branches. — The  vertebral  branch  runs  upward  through  transverse 
processes  of  the  vertebrae  to  the  brain. 

The  internal  mammary  branch  runs  downward  inside  the  chest 
behind  the  ribs  (giving  some  arteries  to  the  mammary  gland),  into 
the  abdominal  muscle. 


Fig.  123. — Subclavian  and  Axillary  Arteries  (Testut). 

The  thyroid  axis  is  a  short  trunk;  it  gives  a  branch  to  the 
thyroid  gland  and  others  to  the  neck  and  shoulder. 

An  axis  (artery)  is  a  short  vessel  dividing  at  once  into  two  or  three. 

The  axillary  artery  is  a  continuation  of  the  subclavian.  It 
begins,  therefore,  where  the  subclavian  ends — in  the  apex  of  the 
axilla,  at  the  lower  border  of  the  first  rib — and  continues  through 
the  axillary  space'  (Fig.  123). 

'  .Axillary  space,  p.  300. 


172 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


Branches  {thoracic,  subscapular,  circumflex.) — To  all  structures 
around  the  axilla.  One,  the  lateral  thoracic,  gives  arteries  to  the 
mammary  gland. 

The  brachial  artery  begins  where  the  axillary  ends,  at  the 
lower  border  of   the  axilla,  or   armpit,  and  extends  downward  in 


Fig.  124. — Deep  Palmer  Arch. 

Made  by  continuation  of  the  radial  artery.     This  is  covered  by  the  muscles  of  the 

thenar  and  hypo  thenar  eminences. 

front  of  the  arm  (with  the  biceps  muscle)  to  the  bend  of  the  elbow, 
where  it  divides  into  the  radial  and  the  ulnar  arteries.  Its  branches 
supply  the  muscles  of  the  humerus  and  the  bone  itself.  (The 
median  nerve  lies  next  to  this  artery  under  the  border  of  the  biceps 
muscle.)     (Figs.  123,  125.) 


RADIAL    AND    ULNAR   ARTERIES. 


^n 


The  radial  and  the  ulnar  arteries  pass  downward  in  the  radial 


and  ulnar  sides  of  the  fore- 
arm to  the  hands.  The  radial 
supplies  the  muscles  in  front 
of  the  radius,  and  winds  to 
the  back  of  the  wrist  to  find 
its  way  to  the  palm  by  pass- 
ing forward  between  the  first 
two  metacarpal  bones.  It 
forms  the  deep  palmar 
arch,  which  crosses  the 
palm  under  the  long  tendons 
(Fig.  124). 

The  ulnar  supplies  the 
muscles  in  front  of  the  ulna, 
and  forms  the  superficial 
palmar  arch,  which  crosses 
over  the  long  tendons  in  the 
palm  (Fig.  125). 

Note. — The  superficial  arch 
crosses  the  palm  opposite  the  level 
of  the  web  of  the  thumb  when  put 
"on  the  stretch."  The  deep  arch 
crosses  about  a  finger- width  nearer 
the  wrist. 

The  digital  arteries  run  in  the 
sides  of  the  fingers;  they  are 
branches  of  the  superficial  arch. 

Clinical  note.^The  pulsation 
of  the  radial  artery  is  easily  felt 
above  the  wrist  in  front,  next  to 
the  tendon  of  the  radial  flexor  of 
the  wrist. 

Surgical  note. — A  direct  com- 
munication exists  between  the 
deep  and  superficial  arches,  con- 
sequently severe  hemorrhage  easily 
occurs  in  the  palm,  since  blood 
will  flow  from  radial  and  ulnar 
arteries  at  one  and  the  same  time, 
and  it  is  sometimes  necessary  to  ligate  both 


Axillary  artery 


Median  nerve 
Brachial  artery 


Lateral  cord 


Pectoral 
muscle 


Ulnar  nerve  and 

artery 
Radial  nerve  and 

artery 


Branches  to  hand 


Fig.  i2<;. — Axillary,  Brachial,  Radial  and 
Ulnar  Arteries.     Superficial  Arches. 


174  anatomy  and  physiology  for  nurses. 

Principal  Arteries  of  the  Head  and  Neck. 

The  common  carotid  arteries. — The  right  is  a  branch  of  the 
anonyma;  the  left  is  directly  from  the  arch  of  the  aorta.  They 
proceed  upward  on  either  side  of  the  trachea,  with  the  internal 
jugular  vein  on  the  lateral  side  and  the  vagus  nerve  behind  them. 
They  carry  the  blood  supply  of  the  head  and  neck  (Fig.  121). 

The  common  carotid  divides  at  the  upper  border  of  the  thyroid 
cartilage  into  internal  carotid  for  the  interior  of  the  head,  and 
external  carotid  for  the  exterior  of  the  head  and  the  neck. 


Fig.  126. — Arteries  of  the  Brain  (Morris). 
Cerebral  arteries  pass  from  the  base  of  the  brain  to  all  parts  of  the  surface. 

The  internal  carotid  is  deep  in  the  neck;  it  runs  up  to  the 
head  and  through  the  carotid  canal  into  the  cranial  cavity. 

Principal  branches. — Ophthalmic,  to  eye  and  appendages,  nose, 
and  forehead.  (The  supraorbital  artery  is  a  branch  of  the 
ophthalmic.) 

Middle  cerebral  to  the  brain,  anterior  cerebral  to  the  brain 
(Fig.  126). 


EXTERNAL    CAROTID   AND    TEMPORAL   ARTERIES.  175 

Note. — The  internal  carotid  makes  four  sharp  turns  after  entering  the  carotid 
canal  in  the  petrous  bone,  and  by  this  means  the  force  of  the  current  in  this 
large  vessel  is  modified  before  it  reaches  the  delicate  tissues  of  the  brain.  The 
internal  jugular  vein  and  vagus  nerve  accompany  it  in  the  neck. 

The  external  carotid  artery  supplies  the  face,  and  front  of  the 
neck  and  scalp  (Fig.  127). 

Principal  branches. — Superior  thyroid,  to  the  thyroid  gland 
and  larynx.  Lingual,  to  the  tongue  and  tonsil.  Facial  (or  external 
maxillary)  to  the  face,  soft  palate  and  tonsil.  Occipital,  to  the  back 
of  the  head  and  neck. 

Clinical  notes. — The  external  maxillary  (facial)  artery  runs  tovs^ard  the 
bridge  of  the  nose.  It  sends  two  labial  arteries  to  the  borders  of  the  lips;  and  the 
one  in  the  upper  lip  supplies  a  branch  to  the  septum  of  the  nose,  therefore,  com- 
pression of  the  upper  lip  will  sometimes  stop  "nose-bleed." 

The  lingual  artery  ends  at  the  tip  of  the  tongue,  in  a  branch  (ranine)  which 
might  be  severed  in  cutting  too  freely  for  "tongue-tie." 


Fig.  127.— Facial,  Temporal  and  Occipital  .\rteries. 

Having  given  oflf  its  branches,  the  external  carotid  passes  into 
the  substance  of  the  parotid  gland  and  divides  into  the  temporal 
and  internal  maxillary. 

The  temporal  passes  through  the  parotid  gland  and  across  the 
zygoma  to  the  side  of  the  head,  supplying  temporal  branches  to  the 
scalp.  The  internal  maxillary  runs  between  the  muscles  of  mas- 
tication in  the  infratemporal  fossa  to  the  deep  parts  of  the  face, 


176  ANATOMY   AND    PHYSIOLOGY   FOR   NURSES. 

including  the  nose  and  pharynx.     The  dental  arteries  are  all  derived 
from  this  vessel. 

Collateral  Circulation. — An  important  descending  branch  of  the  occipital 
artery  runs  down  under  the  deep  muscles  of  the  neck  to  unite  with  one  derived 
from  a  branch  of  the  subclavian,  thus  making  a  short  route  between  the  subcla- 
vian and  the  external  carotid;  the  blood  can  flow  in  this  indirect  way  to  the 
head  if  the  external  carotid  be  ligated. 


Principal  Arteries  of  the  Trunk. 

The  thoracic  aorta  extends  from  the  fourth  dorsal  vertebra 
to  the  diaphragm  (Fig.  129). 

Branches. — Intercostal,  11  pairs,  to  the  intercostal  spaces; 
bronchial  to  lung  tissues;^  pericardial  to  pericardium;  esophageal 
to  esophagus,  and  mediastinal  to  glands  and  tissues  between  the 
lungs  (the  mediastinal  space). 

Note. — These  aortic  intercostal  arteries  run  rather  more  than  half  way  to  the 
front,  in  grooves  under  the  borders  of  the  ribs,  accompanied  by  intercostal  nerves, 
and  veins.  * 

The  abdominal  aorta  extends  from  the  opening  in  the 
diaphragm  to  the  body  (lower  border)  of  the  fourth  Imnbar 
vertebra — a  little  above  the  level  of  the  umbilicus  (Fig.  128). 

Branches. — Phrenic  to  the  diaphragm  and  lumbar  (4  pairs)  to 
the  abdominal  wall,  sacral  to  sacrum  and  rectum. 

Branches  to  viscera:  The  celiac  artery,  dividing  into  gastric,  for 
the  stomach;  hepatic,  for  the  liver ;^  splenic  (or  lienal),  for  the  spleen. 

Superior  mesenteric,  to  the  small  intestine  and  these  parts  of  the 
large  intestine,  namely — cecum,  ascending  and  transverse  colon. 

Inferior  mesenteric,  to  the  remainder  of  the  large  intestine, 
namely — descending  and  sigmoid  colon,  rectum. 

Two  renal  arteries,  to  the  kidneys. 

Adrenal  arteries,  to  the  adrenal  bodies. 

The  ovarian  arteries,  to  the  ovaries,  or  the  spermatic  arteries  to 
the  testes. 

'  Bronchial  arteries  have  very  little  to  do  with  respiration;  they  are  the  nutrient 
arteries  of  the  lungs. 

^  The  hepatic  circulation  is  a  double  one:  Both  venous  and  arterial  blood  enter  the 
liver.  The  portal  vein  (with  products  of  digestion  for  the  liver  to  work  over)  and  the 
hepatic  artery  (with  the  oxygen  with  which  this  work  is  to  be  done)  enter  together  through 
the  portal  fissure.    (The  venous  blood  of  both  leaves  the  liver  by  hepatic  veins,  page  189.) 


BRANCHES    OF    ABDOMINAL   AORTA. 


177 


The  ovarian  artery  runs  downward  into  the  pelvis  and  passes 
between  the  layers  of  the  broad  ligament  to  the  ovary,  freely  supply- 
ing it  and  the  Fallopian  tubes.  It  ends  by  anastomosing  with  the 
uterine  artery  (Figs.  128,  132). 


Cystic  artery 

Hepatic  duct 

Cystic  duct 

Common  duct 

Portal  vein 

istro-duodenal   branch 

iperior  pyloric   branch 

Hepatic  artery 

Right  suprarenal  vein 

ferior  suprarenal  artery 

Renal  artery 

Renal  vein 

Inferior  vena  cava 
Kidney 


Right  spermatic  vein 


Right  spermatic  artery 
Quadratus  lumborum 

muscle 
ight  lumbar  artery  and 
left  lumbar  vein 
Ureteric  branch  of 
spermatic  artery 


Middle  sacral  vessel 


Left  lobe  of  liver 

Esophagus 

Left  phrenic  arterv 

Right  phrenic  arter>' 
Superior  suprarenal 
Gastric  artery 
Inferior  suprarenal 
Splenic  artery 

Left  phrenic  vein 
Left  suprarenal  vein 
Superior  mesenteric 
artery 

Kidney 

Ureteric  branch  of  renal 

Left  spermatic  vein 

Ureter 


Left  spermatic  or 
ovarian  artery 


Inferior  mesenteric  artery 

Ureteric  branch  of 
spermatic 


Ureteric  branch  of 
common  iliac 

Common  iliac  artery 


External  iliac  artery 
Internal  iliac  artery 


Fig.  128. — Branches  of  the  AnnoMiMAL  Aorta  (Morris). 
Note  that  the  right  common  iliac  is  longer  than  the  left. 


The  spennatic  artery  runs  downward  and  along  the  brim  of  the 
pelvis  to  pass  out  through  the  inguinal  canal  with  the  spermatic 
cord;  it  continues  downward  in  the  scrotum  to  supply  the  testes 
(Fig.  128). 


lyS 


ANATOMY   AND    PHYSIOLOGY    FOR   NURSES. 


Special  notes. — The  superior  mesenteric  lies  between  the  layers  of  the 
mesentery.  The  inferior  mesenteric  lies  partly  in  the  left  meso-colon;  it  termi- 
nates as  the  superior  hemorrhoidal  in  the  upper  part  of  the  rectum. 

The  gastric  artery  follows  the  lesser  curve  of  the  stomach,  and  is  frequently 
called  the  coronary  artery.  The  hepatic  and  splenic  both  send  large  branches  to 
the  greater  curve  of  the  stomach,  and  also  to  the  pancreas  and  duodenum,  before 
reaching  the  liver  and  spleen. 


Superior  vena 
cava 


Azygos  major 


Veins 


Inferior  vena 
cava 


The  abdominal  aorta  divides  (bifurcates)  at  the  lower  border  of 
the  fourth  lumbar  vertebra  into  the  right  common  iliac  and  the  left 
common  iliac  (Fig.  128). 

The  two  common  iliac  arteries  diverge  and  v^^hen  they  reach 
the  sides  (right  and  left)  of  the  lumbo-sacral  joint,  each  divides  into 
hypogastric  (or  internal  iliac)  and  external  iliac  (see  Fig.  128). 


BRANCHES  OF  HYPOGASTRIC  ARTERY. 


179 


The  hypogastric  artery  passes  into  the  pelvis  and  gives  off 
branches  which  supply  the  parts  within  and  without  the  pelvic 
wall,  including  the  perineum,  and  all  of  the  pelvic  viscera  except 
the  ovaries. 


Cecum 


Appendix 


Fig.  1.30. — Superior  Mesenteric  Artery  anx»  Vein  (Morris). 
Supplying  the  whole  of  the  small  intestine,  and  about  one-half  of  the  large  intestine. 


Visceral  branches. — Middle  hemorrhoidal,  to  the  rectum/ 

Vesical  (two)  to  the  bladder. 

Uterine  to  the  uterus. 

Vaginal  (several)  to  the  vagina. 

'  The  blood-vessels  of  the  rectum  are  called  hemorrhoidal;  those  of  the  bladder, 
vesical. 


,i8o 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


The  uterine  artery  (Fig.  132)  passes  between  the  layers  of  the 
broad  ligament  to  the  cervix  of  the  uterus,  then  runs  upward  along 
the  side  of  the  body,  supplying  it  freely  with  blood,  and  anastomos- 
ing with  the  ovarian  artery. 

The  arteries  of  the  organs  in  the  lower  part  of  the  pelvis  are 
numerous.  There  are:  three  (or  four)  vaginal  arteries,  three  (or 
more)  vesical  arteries,  three  hemorrhoidal  arteries,  all  derived  from 


Mesenteric 
branches 


Middle  sacral 


Colic  artery 


Inferior 
mesenteric 
artery 


Iliac  vein 


%        Sigmoid  vessels 


4^ Surerior 

hemorrhoidal 


Rectum 


Fig.  131. — Inferior  Mesenteric  Artery  (Morris). 
Supplying  a  portion  of  large  intestine  only,  ending  as  hemorrhoidal. 


the  hypogastric  or  its  branches,  except  the  superior  hemorrhoidal 
which  is  the  terminal  portion  of  the  inferior  mesenteric. 

There  are  also  two  perineal  arteries. 

These  all  anastomose  freely  with  each  other  and  with  other 
arteries,  so  that  a  wound  in  this  region  is  followed  by  an  abundant 
flow  of  blood  from  more  than  one  vessel. 


ARTERIES    OF    LOWER   EXTREMITY. 


l8l 


Note. — The  hypogastric  arteries  in  the  fetus  are  large.  After 
gi\'ing  off  their  branches  they  turn  upward  to  the  umbihcus  where 
they  leave  the  body  of  the  child,  and  become  the  two  umbilical 
arteries  twining  around  the  umbilical  vein  in  the  umbilical  cord. 
After  birth,  these  portions  of  the  vessels  no  longer  transmit  blood 
but  dwindle  to  fibrous  cords  lying  close  to  the  anterior  abdominal 
wall. 


Uterine    Branch  to  round  Fimbriated  extremity  of 

branch  hgament  Fallopian  tube 


Cervical 

branch  of 

uterine  artery 


Uterine  artery 
Hypogastric  artery 


Vaginal  arteries 


Azygos  artery  of  vagina 

Fig.  132. — Uterine  and  Ovarian  Arteries. 
(Uterine,  a  branch  of  hypogastric;  ovarian,  a  branch  of  aorta, 
location  of  the  ureter  (Morris). 


Note  the 


Principal  Arteries  of  the  Lower  Extremity. 

The  external  iliac  distributes  its  branches  almost  entirely  to 
the  lower  extremity.  It  is  about  four  inches  long  and  follows  the 
brim  of  the  pelvis  to  the  inguinal  ligament  where  it  becomes /ewom/. 

Collateral  circulation. — The  inferior  epigastric  branch  of  the  external  iliac 
anastomoses  with  the  superior  epigastric  branch  of  the  internal  mammary,  in 
the  substance  of  the  rectus  muscle,  thus  making  an  indirect  route  from  the  arch 
of  the  aorta  to  the  iliac  vessels  if  the  abdominal  aorta  or  iliac  artery  be  ligated. 


l82 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


Femoral 
artery 

Femoral 
vein 


Deep 

branch 


The  femoral  artery  (Fig.  133)  is  a  continuation  of  the  external 
iliac,  passing  through  the  femoral  trigone  and  the  adductor  canal  to 

the  popliteal  space/  where  it 
becomes  the  popliteal  artery.  Its 
branches  supply  the  skin  and 
fascia  of  the  abdomen  and  ex- 
ternal genital  organs,  and  all 
structures  of  the  front  and  sides 
of  the  thigh.  The  largest  branch 
is  called  the  deep  femoral,  which 
lies  close  to  the  medial  side  of 
the  femur  and  gives  three  perfor- 
ating branches  to  pass  through 
the  adductor  magnus  muscle 
and  supply  the  back  of  the 
thigh. 

Note. — The  femoral  vein  is 
on  the  medial  side  of  the  femoral 
artery  until  it  reaches  the  popli- 
teal space. 

The  popliteal  artery  is  a  con- 
tinuation of  the  femoral,  begin- 
ning at  the  end  of  the  adductor 
canal  (the  opening  in  the  ad- 
ductor magnus)  and  running 
through  the  popliteal  space.  Its 
branches  supply  the  boundaries 
and  floor  of  the  space  and  the 
knee-joint;  it  divides  into  an- 
terior and  posterior  tibial  arteries 

(Fig-  134)- 

The    anterior    tibial    (Fig. 
143)  comes  forward  between  the 
tibia   and   fibula,  supplying  the 
front  of  the  leg;  it  then  becomes 
Fig.  I33--THE  Femoeal  Artery.  ^^^     dorsalis     pedis     (upon     the 

.dorsum  of   the   foot),   ending  between  the  first  and  second  toes. 

-      -  See  p.  303,  Popliteal  Space. 


Anterior  tibial 
nerve 


.Ant 


enor  tibial 
artery 


VEINS.       DEEP   AND    ARTIFICIAL. 


183 


gf^ACeuS\/»e 


m¥ 


>  Gluteal  n. 


^r 


Z~i^^'fo._^, 


Sciatic  n. 


^j\y 


^ 


Popliteal  artery 
Tibial  n. 

.  Peroneal  n. 


The  anterior  tibial  passes  in  front  of  the  ankle-joint,  with  the  Ion 
tendons  of  the  toe  muscles. 

The  posterior  tibial  (Fig.  134) 
supplies  the  back  of  the  leg  and 
sole  of  the  foot.  It  lies  between 
the  calf  muscles  and  the  deep  mus- 
cles, and  runs  behind  the  medial 
malleolus,  dividing  then  into  medial 
and  lateral  plantar  arteries  for  the 
medial  and  lateral  portions  of  the 
sole,  or  plantar  region. 

The  Veins. 

All  veins^  run  toward  the  heart. 
Beginning  as  very  small  vessels 
formed  by  the  union  of  capillaries, 
they  unite  and  reunite  until  they 
make  two  sets  of  larger  vessels 
called  the  deep  and  superficial  veins. 

The  deep  veins  accompany 
arteries,  being  enclosed  in  the  same 
sheath  with  them,  and  receiving 
veins  corresponding  to  the  branches 
of  these  arteries.  Arteries  of  me- 
dium size  usually  have  two  com- 
panion veins  (or  venae  comites); 
large  ones  have  but  one,  and  it 
sometimes  bears  a  name  differing 
from  that  of  the  artery.  (Example 
— internal  carotid  artery,  internal 
jugular  vein.) 

The  superficial  veins  do  not 
usually  accompany  arteries.  They 
lie  in  the  superficial  fascia,  gather- 
ing  blood   from   skin    and   fascia, 

and  many  of  them  are  called  cutane- 

\T        c  i.1     it-     J  ]       Fig.  1^4. — The  Popliteal  Artery. 

ous.     Very  frequently  the  deep  and  ■^^ 

superficial  veins  communicate,  through  short  connecting  branches. 

'  The  names  of  all  of  the  veins  are  given  in  tabular  form  on  page  378.     Only  the 
principal  ones  are  here  describeri. 


.  Ant.  tib.  artery 


Tibial  n. 


Post.  tib.  artery 


184  anatomy  and  physiology  for  nurses. 

Principal  Veins  of  the  Head  and  Neck  (Figs.  127,  139). 

Deep. — From  the  deep  face  and  cranial  cavity;  they  empty 
into  the  internal  jugular  vein  (Figs.  121,  127). 

The  internal  jugular  is  a  continuation  of  the  transverse  sinus, 
(a  venous  channel  inside  the  skull,  which  ends  at  the  jugular  fora- 
men). This  vein  lies  on  the  lateral  side  of  the  internal  carotid 
artery  in  the  upper  part  of  the  neck,  and  further  down  at  the  side 
of  the  common  carotid  artery,  with  the  vagus  nerve  between  and 
behind  them.     It  ends  by  uniting  with  the  subclavian  vein. 


Fig.  135. — Deep  Arteries  in  Sole  of  Foot. 
I,  Internal  plantar;  2,  external  plantar  (Holden). 

Superficial. — From  the  scalp,  ear,  and  face,  bearing  the  names 
of  the  arteries  (usually) ;  they  empty  into  the  external  jugular  vein 
.which  opens  into  the  subclavian. 

There  are  many  veins  in  the  spongy  bone  between  the  compact  layers  of 
cranial  bones,  and  these  communicate  by  emissary  veins  with  the  sinuses  and 
also  with  the  scalp  veins. 

Principal  Veins  of  the  Upper  Extremity. 

Deep. — ^From  the  hand  and  wrist;  they  form  ulnar  and  radial 
veins  (running  with  arteries  of  the  same  name)  which  unite  to  form 
brachial  veins. 

The  brachial  veins  in  turn  unite  to  form  the  axillary,  and  the 
axillary  becomes  subclavian. 

The  external  jugular  vein  empties  into  the  subclavian  at  about  the  middle  of 
the  clavicula.     It  is  easily  seen  through  the  platysma  muscle. 

Superficial. — From  fore  arm;  groups  of  veins,both  anterior  and 
posterior,  form  two,  called  the  basilic  and  cephalic,  which  empty  into 
the  axillary  vein. 

A  median  vein  in  front  of  the  elbow  connects  the  basilic  and  the  cephalic. 
Fig.  136. 


SUPERFICIAL    VEINS    OF    EXTREMITIES. 


185 


Ulnar 
vein 


^^^ 


Fig.  1.36. — Superficial  Veins, 
Upper  Extremity. 


Fig.  137. — Superficial  Veins, 
Lower  Extremity. 


i86 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


The  subclavian,  having  gathered  blood  from  the  entire  upper 
extremity,  unites  with  the  internal  jugular  to  form  the  innominate 

vein;  the  anonyma  veins  {right  and  left) 
unit  to  form  the  superior  vena  cava. 
The  left  anonyma  vein  is  the  longer 
of  the  two,  since  it  must  cross  to  the 
right  side  to  join  the  right  vein. 

The  Superior  Vena  Cava. 

The  superior  vena  cava  is  formed 
by  the  union  of  the  two  anonyma 
veins.  It  lies  on  the  right  side  of  the 
arch  of  the  aorta,  and  opens  into  the 
right  atrium  of  the  heart  (Fig.  121), 

Veins  of  the  Thorax. 

Blood  from  all  of  the  intercostal 
veins  (except  in  the  first  space)  finally 
reaches  the  great  azygos  vein,  which 
opens  into  the  superior  vena  cava 
(Fig.  129). 

The  blood  of  the  heart  itself  is 
returned  directly  to  the  right  atrium 
by  a  coronary  vein  called  the  coronary 
sinus.  All  other  thoracic  organs  re- 
turn their  blood  to  azygos  veins  and 
these  to  superior  vena  cava. 

Summary. 

The  venous  blood  from  all  struc- 
tures above  the  diaphragm  (except 
the  heart)  is  returned  through  the 
superior  vena  cava  to  the  right  heart 
(right  atrium)   (p.  165). 

Principal  Veins  of  the  Lower 
Extremity. 

Deep. — ^From  the  dorsum  of  the 
foot  the  veins  form  the  anterior  tibial  veins;  from  the  sole  of  the 
foot,  the  posterior  tibial. 


Fig.  138. 


—Superficial  VEnsrs, 

ANTERIOR. 


THE    INFERIOR    VENA    CAVA. 


187 


The  tibial  veins  unite  to  form  the  popliteal,  which  continues  as 
the  femoral,  and  these  two  veins  receive  others  corresponding  in 
name  to  the  branches  of  the  arteries  which  they  accompany. 

Superficial. — From  the  lateral  part  of  the  foot  and  leg,  by  the 
small  saphena  vein,  to  the  popliteal  (Fig.  137). 

From  the  dorsum  and  medial  part 
of  the  foot  and  leg  by  the  great  saphena 
vein  to  the  femoral,  passing  through  the 
oval  fossa  in  the  fascia  lata,  below  the 
inguinal  ligament  (Fig.  138).  The 
femoral  vein  becomes  external  iliac. 

\^Eixs  OF  THE  Pelvis  and  Abdomen. 

The  veins  of  the  pelvic  organs  are 
large  and  numerous. 

In  the  vaginal  walls  and  around  the 
lower  end  of  the  vagina,  also  in  the 
rectum  especially,  they  form  close  net- 
works or  plexuses  which  when  wounded 
bleed  profusely.  The  veins  of  the  anal 
canal  are  prone  to  become  congested  and 
assume  a  varicose  condition  constituting 
hemorrhoids. 

The  pelvic  veins  empty  into  the 
hypogastric,  and  the  hypogastric  and 
external  iliac  veins  unite  to  form  the 
common  iliac. 

The  right  and  left  common  iliac  veins 
unite  to  form  the  inferior  vena  cava 
(Fig.  139). 

The  Inferior  Vena  Cava. 


Fig.  139. — Showing  Forma- 
tion OF  THE  Large  Veins. 
I,  Superior  vena  cava,  2,3, 
innominate  veins;  4,  right  sub- 
clavian; 5,6,  int.  and  ext.  jugu- 
lar veins;  8,  inferior  vena  cava; 
14,  common  iliac  veins.  (Re- 
maining references  not  given.) 
(Holden.) 


This  is  formed  by  the  union  of  the 
two  common  iliac  veins  at  the  right  side 
of  the  bifurcation  of  the  adbominal  aorta  (at  the  level  of  the 
lower  border  of  the  fourth  lumbar  vertebra).  It  runs  upward 
through  the  abdomen,  on  the  right  side  of  the  aorta,  close  to  the 
spinal  column,  to  pass  through  the  diaphragm  and  enter  the 
pericardium  and  right  atrium  of  the  heart. 


1 88  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

From  the  abdominal  walls  the  phrenic  and  lumbar  veins  open 
into  the  inferior  vena  cava. 

From  abdominal  viscera  the  renal  and  adrenal  veins  open  into 
the  inferior  vena  cava. 


Fig.  140. — Scheme  of  Formation  of  Portal  Vein,  by  Veins  from  Spleen, 
Stomach  and  Intestines. 

The  right  ovarian  and  right  spermatic  veins  open  into  the  in- 
ferior vena  cava;  the  left  ovarian  and  left  spermatic  veins  open  into 
the  left  renal  vein  which  carries  their  blood  to  the  inferior  vena  cava. 

The  splenic  (or  lienal),  gastric,  and  mesenteric  veins  form  the 


THE    PORTAL   CIRCULATION.  189 

portal  vein,  which  is  four  inches  long  and  enters  the  liver  at  the 
transverse  fissure  or  porta  (Figs.  io6,  140). 

THE  PORTAL  CIRCULATION. 

This  is  the  circulation  of  venous  blood  through  the  liver.  The 
portal  vein  bears  the  products  of  digestion  from  stomach  and 
intestines;  entering  the  liver  it  divides  into  branches  which  form 
an  extensive  net-work  in  its  substance. 

Having  been  distributed  through  these  fine  capillaries,  the 
blood  leaves  the  liver  by  the  hepatic  veins,  which  open  directly  into 
the  inferior  vena  cava. 

SUMMARY. 

The  venous  blood  from  all  structures  (practically)  below  the 
diaphragm,  is  returned  through  the  Inferior  Vena  Cava  to  the 
heart  (right  atrium). 


Opening  closed  by 
tricuspid  valve    " 
Foramen  ovale 

Coronary  sinus 
Location  of  Eus- 
tachian valve 


Fig.  141. — Infant's  Heart. 
Showing  interior  of  right  atrium  (Holden). 

THE  FETAL  CIRCULATION. 

The  fetus  is  nourished  by  blood  brought  from  the  uterine 
(placental)  arteries  of  the  mother,  through  a  special  vessel  called 
the  umbilical  vein.  After  circulating  in  the  body  of  the  child 
it  is  returned  to  the  placenta  by  two  special  vessels  called  the 
umbilical  arteries.     (Fig,  142.) 

During  intrauterine  life  the  lungs  do  not  contain  air,  therefore, 


I  go  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

the  interchange  of  oxygen  and  carbon  dioxid  in  the  blood  must  be 
accomplished  elsewhere.  This  also  is  brought  about  by  means  of 
the  placental  vessels. 

The  plan  of  fetal  circulation  requires  still  other  special  provision, 
namely : 

The  foramen  ovale. — An  opening  in  the  septum  between  the 
two  atria  (Fig.  141). 

The  Eustachian  valve. — A  fold  of  endocardium  in  the  R. 
atrium,  (so  placed  as  to  direct  the  blood  from  the  inferior  vena 
cava  through  the  foramen  ovale). 

The  ductus  arteriosus. — A  short  trunk  (1/2  inch  long)  which 
connects  the  pulmonary  artery  with  the  arch  of  the  aorta. 

The  course  of  the  blood  is  as  follows:  Arterial  blood  is  brought 
through  the  umbilical  vein  which  enters  the  body  at  the  umbilicus, 
runs  upward  under  the  liver  giving  branches  to  that  organ;  and 
terminates  (as  the  ductus  venosus)  by  opening  into  the  inferior  vena 
cava,  just  below  the  diaphragm.  It  flows  at  once  into  the  right  atrium- 
of  the  heart,  where  it  is  guided  by  the  Eustachian  valve  through  the 
foramen  ovale  into  the  left  atrium;  from  there  it  passes  into  the  left 
ventriculum  an^  through  the  aorta,  to  be  distributed. 

The  greater  portion  of  this  current  goes  to  the  head  and  upper 
extremities,  from  which  it  returns  to  the  right  atrium  again  and 
passes  down  into  the  right  ventriculum;  thence  into  the  pulmonary 
artery,  but  not  to  the  lungs  (except  a  very  small  portion);  it  is 
delivered  instead  by  the  ductus  arteriosus  to  the  aorta,  at  a  point 
where  the  arch  begins  to  descend,  and  joins  the  small  current  already 
there,  to  supply  the  trunk  and  lower  extremities. 

The  greater  portion  of  this  blood  leaves  the  fetus  before  it 
reaches  the  lower  extremities,  by  way  of  the  two  umbilical  arteries, 
and  returns  to  the  placenta  for  re-oxygenation;  while  that  which 
goes  to  the  lower  extremities  is  later  emptied  into  the  inferior  vena 
cava  to  be  again  mixed  with  blood  from  the  umbilical  vein  on  its 
way  to  the  fetal  heart. 

Notes. — The  liver  is  the  only  organ  to  receive  blood  just  as  it  comes  from 
the  mother;  the  baby's  liver  is  very  large.  The  head  and  upper  extremities 
are  next  supplied,  although  v^'ith  a  slight  admixture  of  venous  blood  (which 
came  through  the  inferior  vena  cava);  they  are  vi^ell  developed.  The  pelvis 
and  lov^rer  extremities  receive  but  a  small  supply  of  venous  vi^ith  a  slight 
admixture  of  arterial  blood;  they  are  not  so  well  developed. 


THE    FETAL   CIRCULATION. 


191 


< 


--X 


Fig.  142. — The  Fetal  Circulation  (Morris). 


192  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

The  placenta. — The  placenta  is  formed  in  a  portion  of  the  linmg 
membrane  of  the  uterus,  by  an  intricate  arrangement  of  the  uterine 
vessels  of  the  mother  with  the  umbilical  vessels  of  the  fetus.  It  is 
here  that  the  umbilical  arteries  coming  from  the  fetus,  end;  and 
the  umbilical  vein  going  to  the  fetus,  arises.  Here  also  the  inter- 
change of  gases  and  of  waste  and  nutritive  matter  between  fetal  and 
maternal  blood,  is  carried  on. 

The  umbilical  cord  connects  the  placenta  and  the  fetus.  It 
comprises  the  two  arteries  and  the  one  vein,  protected  by  a  gelatinous 
substance  or  "Wharton's  jelly,"  in  which  they  are  embedded. 

PHYSIOLOGY  OF  THE  BLOOD. 

We  have  learned  that  the  nutritious  portions  of  the  food  are, 
after  digestion,  poured  into  the  blood  and  circulated  throughout 
the  body;  also  that  cell  action  results  in  waste  which  is  returned  to 
the  blood.  Again,  that  tissue  changes  are  chemical  in  their  nature 
and  chemical  action  is  accompanied  by  heat;  this  is  imparted  to 
the  blood,  which  can  in  turn  convey  heat  to  other  parts. 

Here  then,  are  three  important  functions  of  the  blood: 

1.  To  convey  food  (including  oxygen  from  the  lungs)  to  the 
tissues.^ 

2.  To  convey  waste  (including  carbon  dioxide)  from  the  tissues. 

3.  To  equalize  the  hody  temperature.     Add  to  these: 

4.  To  provide  water  for  dissolving  waste  substances  to  be 
removed  from  the  body  by  skin,  kidneys  and  intestine. 

5.  To  be  a  medium  for  transporting  internal  secretions  (page  220). 

6.  To  furnish  its  own  remedy  for  hemorrhage  by  bearing  the 
factors  of  coagulation. 

(The  blood  is  the  source  of  water  supply  as  well  as  food  supply 
for  the  body.) 

The  special  functions  of  the  hlood  cells  have  been  outlined,  ' 
namely:     The  oxygen-hearing  property  of  red  cells  and  the  phago- 
cytic power  of  the  white. 

Any  irritation  of  the  tissues  is  promptly  followed  by  an  increase  in 
the  blood  and  lymph  supply  of  the  part,  and  (if  long  continued) 
crowding  of  cells  in  the  capillaries.  The  leucocytes  put  forth  little 
prolongations  of  their  substance  which  penetrate  the  vessel  wall, 

^  It  must  not  be  forgotten  that  oxygen  makes  tissue  changes  possible — hence  the  im- 
portance of  the  blood  as  an  oxygen  carrier. 


PHYSIOLOGY   OF   BLOOD.  I93 

and  gradually  the  cells  themselves  work  their  way  through.  This 
causes  a  hardened  or  indurated  condition  which  will  soon  disappear 
if  not  excessive^  but  with  severe  irritation  the  process  goes  on  to 
inflammation  (the  cells  crowding  each  other  to  death)  and  pus 
results. 

In  case  of  bacterial  invasion,  the  leucocytes  surround  and  absorb 
the  offending  organisms,  thus  protecting  the  body  from  the  effects 
of  their  toxins.  This  they  are  doing  continually  because  we  are 
constantly  taking  bacteria  of  various  sorts  into  our  systems.  So 
long  as  the  number  is  not  too  great  the  phagocytes  can  take  care  of 
them,  it  is  only  when  there  are  too  many,  that  they  cannot  be  over- 
come. It  is  due  to  the  character  of  the  capillary  walls,  that  the 
blood  cells  can  migrate  into  the  tissues  (diapedesis). 

Consisting  as  it  does  of  a  single  layer  of  endothelial  cells,  the 
capillary  wall  also  renders  possible  the  interchange  of  fluids  between 
the  blood-vessels  and  the  tissues.  This  interchange  is  accomplished 
by  the  physical  process  of  osmosis,  which  may  be  defined  as  the 
diffusion  of  two  liquids  or  solutions  through  an  intervening 
membrane. 

Simple  diffusion  is  the  mixing  of  two  liquids  when  poured  together,  to  form  a 
uniform  solution. 

Filtration  is  the  passing  of  a  liquid  through  a  membrane  or  other  substance 
for  the  purpose  of  removing  some  portion  altogether. 

It  is  probable  that  all  three  processes  go  on  in  the  tissues. 


13 


CHAPTER  XII. 
THE  LYMPHATIC  SYSTEM. 

The  l)rmphatic  system  comprises  an  extensive  arrangement  of 
lymph  vessels  or  lymphatics,  and  lymph  nodes  or  glands — both 
deep   and  superficial  (Fig  143). 

This  system  pervades  the  entire  body  for  the  circulation  of 
lymph — a  nutritive  fluid  derived  from  the  blood.  It  is  by  this 
means  that  foods  which  have  been  absorbed  from  the  digestive 
organs  and  poured  into  the  blood,  are  separated  out  for  the  use  of 
the  tissues  and  conveyed  to  them. 

Ljrmph  spaces. — Between  the  cells  and  collections  of  cells  of 
every  tissue,  except  cuticle,  hair  and  nails,  are  found  minute  tissue 
spaces  or  lymph  spaces,  communicating  freely  with  each  other. 
There  are  also  spaces  around  the  smallest  blood-vessels  and  nerves 
(called  respectively  perivascular  and  perineural  spaces).  These  all 
communicate  with  the  beginnings  of  lymph-capillaries  (just  how, 
is  disputed). 

L3rmph.  capillaries. — ^These  resemble  blood  capillaries  in  that 
they  have  but  a  single  coat  (of  endothelium).  They  permeate  the 
tissues  in  every  direction,  forming  a  close  network,  from  which 
lymph  vessels  or  lymphatics  originate  by  the  uniting  of  small  channels 
to  form  larger  ones  (as  veins  originate). 

Lymph  vessels. — Are  delicate  and  transparent,  but  have  three 
flexible  coats.  (One  elastic,  two  fibro-muscular.)  They  are  pro- 
vided with  valves,  formed  by  folds  of  the  lining  at  very  short  intervals, 
which  give  the  appearance  of  beading  to  the  vessels.  This  arrange- 
ment allows  the  lymph  to  flow  toward  the  heart  but  prevents  it 
from  moving  in  the  other  direction. 

The  lymph  vessels  of  the  intestines  have  been  called  lacteals 
because  of  their  milky  appearance  during  the  process  of  digestion 
the  whitish  color  being  due  to  the  presence  of  fat  globules  trans- 
mitted by  the  lymph  capillaries  of  the  villi.  This  fat-bearing 
lymph  is  called  chyle. 

194 


LYMPH    VESSELS. 


195 


Within  the  tissues  of  the  body  the  lymph  vessels  are  too  small 
to  be  seen  by  the  naked  eye,  but  they  unite  again  and  again,  to 
form  larger  ones  (although  still  very  small)  which  in  some  places 
may  be  seen  entering  or  leaving  glands,  until  finally  two  remain — • 
the  right  lymphatic  duct  and  the  thoracic  duct,  which  have  a  diameter 
of  3  or  4  mm. 

Lymph  is  a  transparent  watery  saline  fluid  with  lymph  corpuscles 
floating  therein.  It  contains  nutritive  substances  for  the  tissues  and 
waste  matters  derived  from  them. 


■'f.l-...^5'U'.- 


t'lG.  143. — Lymphatic  Vessels  and  Nodes. 
I  and  2  are  portions  of  the  Thoracic  Duct  (Holden). 

The  description  of  plasma  applies  very  well  to  lymph,  always  keeping  in 
mind  that  lymph  is  more  watery  and  carries  lymph  cells  while  plasma  bears  blood 
cells;  also  it  will  coagulate,  but  slowly  and  not  so  firmly,  with  a  pale  clot  because 
of  the  absence  of  red  cells. 

The  origin  of  lymph  is  primarily  from  the  blood.  The  walls  of 
the  blood-capillaries  allow  a  transudation  of  thin  plasma  or  serum 


196  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

into  the  tissue  spaces,  and  this  is  the  source  of  nutritive  principles. 
Waste  matters  are  added  as  the  result  of  the  activities  of  the  tissues 
themselves;  they  represent  the  '^tissue  wasted  This  fluid,  conveyed 
by  lymph-capillaries  to  lymph-vessels  is  carried  to  lymph  glands, 
where  it  gathers  the  lymph  corpuscles  which  float  in  it. 

Lymph  glands  or  lymph  nodes  are  small  round  or  oval  bodies 
of  a  reddish  color,  varying  in  size  from  that  of  a  pin  head  to  a 
small  bean,  and  intersecting  the  lymph  vessels  in  certain  regions  of 
the  body.  They  are  numerous  in  the  neck,  axilla  and  groin,  also 
in  the  thorax  and  abdomen. 

A  lymph  gland  is  invested  with  a  thin  but  firm  capsule  (fibro- 
muscular)  which  sends  septa  or  partitions  into  the  interior,  to 
support  the  gland  substance  in  small  compartments.  The  gland 
substance  lies  loosely  in  this  capsule  and  in  the  compartments, 
leaving  spaces  for  the  passage  of  lymph  around  the  different  por- 
tions and  around  the  whole.  It  contains  great  numbers  of  young 
corpuscles,  which  are  added  to  the  lymph  stream  as  it  washes 
through  the  gland,  and  appear  later  as  the  lymphocytes  of  the  blood. 

L5miph  is  brought  to  the  glands  by  afferent  lymph  vessels, 
usually  several  for  each  gland.  After  flowing  through  the  various 
spaces  in  and  around  the  gland  substance,  it  leaves  by  efferent 
vessels,  which  unite  to  carry  the  stream  on  its  way  toward  the 
large  veins. 

A  specimen  taken  from  an  efferent  vessel  and  examined  under  the  microscope 
will  show  a  greater  number  of  lymphocytes  than  one  taken  from  an  afferent 
vessel. 

Clinical  notes. — ^Edema  is  an  accumulation  of  lymph  in  the  tissue  spaces. 
We  have  seen  that  an  interchange  between  the  blood  and  lymph  capillaries  is 
continually  going  on,  the  blood  providing  lymph,  the  tissues  receiving  it,  abstract- 
ing nutriment  and  adding  waste;  returning  it  to  the  blood,  but  in  less  quan- 
tity than  was  received;  the  excess  which  remains  in  their  spaces  being  carried 
by  lymph  vessels  to  the  venous  blood. 

Should  this  balance  of  interchange  be  disturbed,  the  effect  is  evident  at  once. 
A  too  abundant  supply,  or  an  obstruction  to  the  outflow,  would  overwhelm  the 
tissues  with  fluid,  causing  edema. 

Clinical  Notes. — Inflammation  of  serous  membranes,  if  severe, 
results  in  the  accumulation  of  lymph  or  serum  in  their  cavities — 
this  is  an  effusion. 

Inflammation  in  the  tissues  themselves  causes  an  excess  of 
lymph  accompanying  the  increased  flow  of  blood.     The  accumu- 


LYMPH    DUCTS.  1 97 

lation  of  lymph  with  leucocytes  and  red  cells  from  the  blood,  causes 
induration. 

The  largest  lymph  vessel  is  called  the  thoracic  duct  (Fig.  121). 
It  is  about  18  inches  long,  having  an  average  diameter  of  a  small 
goose-quill.  It  begins  at  the  second  lumbar  vertebra,  in  a  litde 
pouch  called  the  receptacle  of  the  chyle  (or  receptaculum  chyli)  and 
runs  up  behind  the  aorta,  through  the  diaphragm.  It  then 
continues  upward  through  the  thorax  to  the  level  of  the  seventh 
cer\'ical  vertebra,  where  it  arches  to  the  left  to  open  into  the  sub- 
clavian vein,  at  the  junction  with  the  left  internal  jugular.  Thus  the 
lymph  and  chyle  join  the  current  of  venous  blood  on  its  way  to  the 
heart  for  circulation  and  distribution. 

The  right  lymphatic  duct  is  a  short  vessel,  a  half  inch  in 
length,  which  opens  into  the  right  subclavian  vein  at  the  junction 
with  the  right  internal  jugular.  Through  this  channel  lymph  alone 
joins  the  venous  blood  on  its  way  to  the  heart. 

Note. — The  cavities  of  serous  membranes,  as  peritoneum,  pleura, 
pericardium  and  others,  belong  to  the  system  of  lymph-spaces,  but 
of  a  special  kind.  They  are  surrounded  by  capillaries  which  com- 
municate with  them  by  tiny  openings  in  the  membrane,  called 
stomata. 

SITUATION  OF  THE  PRINCIPAL  GROUPS  OF  GLANDS 

OR  NODES. 

Below  the  Dmphragm. 

Lower  extremity. — Popliteal,  in  the  popliteal  space,  inguinal 
(important)  at  the  oval  fossa  and  along  the  inguinal  ligament 
(Fig.  145). 

Pelvis :  External  and  internal  iliac,  with  the  external  and 
internal  iliac  vessels. 

Abdomen :  Mesenteric,  between  the  layers  of  the  mesentery 
(about  150);  lumbar,  in  front  of  the  aorta  and  vena  cava.  These 
are  numerous. 

Above  the  Dlvphragm. 
Upper  extremity. — Epitrochlear ,  above  the  internal  epicondyle; 
axillary,  under  the  axillary  walls,  and  clavicular,  along  the  subclavian 
vessels  (Fig.  146). 

The  axillary  glanrls  are  superficial,  under  the  borders  of  the  muscle  boundaries;  and 
deep  around  the  axillary  vessels.     These  are  very  important. 


198 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


Head :  Occipital,  below  the  occiput;  auricular,  behind  the  ear; 
parotid,  upon  the  parotid  gland;  submaxillary,  under  the  angle  of 
the  jaw. 

Neck :  Superficial  cervical,  near  the  external  jugular  vein;  deep 
cervical,  with  the  large  vessels  (carotid  arteries  and  internal  jugular 
vein.)     (Important.) 

Thorax :  Mediastinal,  with  the  vessels  in  the  mediastinum;^ 
bronchial,  with  bronchial  tubes  and  vessels — these  are  numerous. 


<//n 


Lacteals 


Veins 


Fig.  144. — Lacteals  and  Mesenteric  Glands  (Morris). 

DIRECTION  OF  THE  LYMPH  STREAM. 

Below  the  Dm.phragm. 

From  the  lower  extremity  up  through  popliteal,  saphenous,  and  inguinal 
glands  to  the  external  iliac,  and'thence  to  the  lumbar  glands. 

From  the  buttock  and  anterior  parts  of  the  genital  organs  to  the  inguinal, 
external  iliac,  and  thence  to  the  lumbar  glands. 

In  the  deeper  parts  of  the  genital  organs  to  the  internal  iliac,  and  thence 
to  the  lumbar  glands. 

From  the  pelvic  organs  or  viscera  to  the  internal  iliac,  and  thence  to  lumbar 
glands. 

The  ovaries,  tubes,  and  fundus  of  the  uterus  send  their  lymph  directly  to 
the  lumbar  glands,  instead  of  first  through  the  internal  iliac. 

From  the  abdomen,  lymph  from  the  abdominal  walls  flows  to  lumbar 
glands  (sometimes  indirectly),  also  from  the  kidneys  and  adrenals  to  the  lumbar 
glands, 

^  See  page  297,  The  mediastinum. 


SUPERFICL\L    LYMPHATICS. 


199 


.^/^ 


Lymph-nodes 


Small  saphena 
vein 


Fig.  145. — The  Lymphatics  and   Lympii-nodes  of  the  Lowtr  Extremity. 


200 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


From  intestines  through  mesenteric  glands  to  the  thoracic  duct;  from  all  rem- 
maining  abdominal  organs  to  the  thoracic  duct  (except  upper  surface  of  the  liver) . 

All  lymph  which  flows  through 
Itunbar  glands  runs  to  the  thoracic 
duct,  and  through  it  to  the  left  sub- 
clavian vein. 

Note. — The  lymphatics  in  the 
mesentery,  coming  from  the  small  in- 
testine, convey  not  only  lymph  but  chyle 
also,  which  is  light  in  color  and  gives  to 
them  a  milky  appearance,  therefore 
their  name,  lacteals  (Fig.  144). 

Above  the  Dl^phragm,  Left 
Side.' 

From    the    left    upper   extremity 

through  axillary  and  subclavian  glands 
to  the  deep  cervical  glands,  thence  to 
thoracic  duct. 

From  left  head  and  neck,  super- 
ficial: face  and  scalp,  to  occipital,  sub- 
maxillary, superficial  cervical,  and  then 
deep  cervical  glands.  Deep:  face,  throat 
and  neck,  to  deep  cervical  glands  and 
thence  to  thoracic  duct. 

From  the  left  thorax,  walls  and 
viscera  (including  left  half  of  heart), 
to  thoracic  duct. 

Above  the  Diaphragm,  Right 
Side. 

From   the  right  upper  extremity 

through  axillary,  subclavian,  and  deep 
cervical  glands,  to  the  right  lymphatic 
duct  (Fig.  121). 

From  the  right  head  and  neck 
through  occipital,  submaxillary,  super- 
ficial and  deep  cervical,  to  right  lymphatic 
duct. 

From  the  right  thorax,  walls  and 
viscera  (including  right  half  of  heart), 
to  right  lymphatic  duct. 

L3miphatics  of  the  mammary 
gland. — Most  of  these  empty  into 
superficial  and  deep  axillary  glands;  a  few  pass  through  the  chest 


Ulnar 
vein 


Fig.  146. — Lmyphatics  and  Nodes  of 
Upper  Extremity. 


METASTASIS.       SUMMARY    OF    FUNCTIONS.  20I 

wall  to  mediastinal  glands,  and  those  of  the  nipple  and  areola  of 
the  two  sides  communicate  with  each  other. 

Summary. 

The  right  lymphatic  duct  gathers  lymph  from  the  right  upper 
extremity,  right  head,  neck,  thorax  and  thoracic  viscera,  and  the 
upper  surface  of  the  liver. 

The  thoracic  duct  gathers  lymph  from  all  other  parts  of  the 
body — that  is,  the  left  side  above  the  diaphragm,  and  all  parts 
helow  the  diaphragm,  except  the  upper  surface  of  the  liver.  The 
two  ducts  empty  into  the  two  subclavian  veins,  and  thus  the  lymph 
joins  the  blood  current. 

Clinical  notes. — Certain  conditions  of  disease  in  an  organ  or  tissue  are 
followed  by  enlargement  of  the  nearest  glands  which  receive  lymph  from  that 
part.  If  the  disease  be  not  arrested,  the  glands  next  in  order  will  suffer,  and  the 
next,  and  the  next. 

Disease  of  the  mammary  gland  will  cause  swelling,  first,  of  the  superficial 
glands  under  the  border  of  the  pectoral  muscle,  and  later  of  the  deep  axillary 
and  clavicular  glands.  Mediastinal  glands  are  sometimes  affected  when  the 
upper  portion  of  the  gland  is  diseased. 

Disease  of  the  tonsils  will  affect  the  submaxillary  and  cervical  glands. 

Disease  of  the  pharynx,  the  cervical  glands. 

Disease  of  the  larynx  will  affect  the  cervical  glands,  and  may  affect  the 
mediastinal  and  bronchial  glands. 

Disease  of  the  upper  extremity  will  cause  swelling  of  the  axillary  glands. 

Disease  of  the  lower  extremity  will  affect  the  saphenous  group  and  the 
inguinal. 

Disease  of  the  external  genital  organs  and  lower  end  of  vagina  will  affect  the 
inguinal  glands  along  the  inguinal  ligament. 

Disease  of  the  neck  of  the  womb  (cervix  uteri)  will  affect  iliac  glands,  while 
disease  of  the  body  of  the  womb  (fundus  uteri),  or  of  ovaries  or  tubes,  will 
affect  lumbar  glands. 

The  transmission  of  the  causes  of  disease  from  one  organ  to  another  by  the 
lymphatics  is  called  metastasis,  it  is  often  seen  to  follow  a  malignant  growth. 

The  Functions  of  the  Lymph  System. 

By  the  lymph  spaces,  to  transmit  nutritive  fluid  from  the  blood 
to  the  tissues,  and  waste  matters  from  the  tissues  to  the  blood. 

By  lymph  capillaries  and  vessels,  to  convey  lymph  to  the  blood , 
in  the  large  veins. 

By  lymph  nodes  or  glands,  to  give  origin  to  lymphocytes,  and  to 
filter  out  and  retain  poispnous  or  injurious  substances  from  the 
lymph  stream. 


CHAPTER  Xm. 
THE  RESPIRATORY  ORGANS  AND  RESPIRATION. 

Respiration  is  breathing. 

Inspiration  is  the  act  of  drawing  air  into  the  lungs;  expiration 
is  the  act  of  expelHng  it.  An  inspiration  and  an  expiration  together 
constitute  a  respiration.  ^ 

The  respiratory  organs  are  the  nose,  pharynx,  larynx,  trachea, 
bronchial  tubes,  and  lungs,  with  the  thorax  and  its  muscles,  including 
the  diaphragm;  and  the  pulmonary  blood-vessels.  These  organs 
constitute  the  respiratory  apparatus  and  they  include  the  res- 
piratory tract,  which  is  a  series  of  channels  or  air-passages  at 
the  termination  of  which  the  air  comes  into  contact  with  the 
respiratory  epithelium. 

The  nose. — The  part  that  is  supported  by  the  nasal  bones  is 
the  bridge  of  the  nose.  The  nostrils  are  the  expanded  portion; 
they  contain  no  bones,  but  small  plates  of  cartilage  instead,  which 
are  moved  by  little  muscles,  therefore,  they  may  be  expanded  or 
contracted. 

The  cavity  of  the  nose  is  divided  into  the  right  and  left  nasal 
cavities  by  a  partition  called  the  septum,  the  anterior  portion  of  the 
septum  being  formed  by  the  triangular  cartilage  of  the  nose,  and 
the  remaining  portion  by  bones — the  vomer  and  the  vertical 
plate  of  the  ethmoid.  The  openings  upon  the  face  are  the  nares 
(anterior  nares)  and  those  at  the  back  (looking  into  the  nasopharynx) 
are  the  choance  (posterior  nares)  (Figs.  95  and  147). 

On  the  lateral  wall  of  each  nasal  cavity  are  the  three  turbinated 
hones  or  shells  (concha),  and  three  spaces  or  passages  directly 
underneath  them,  named  as  follows :  the  superior  meatus  (or  passage) 
beneath  the  superior  concha  (or  shell) ;  the  middle  meatus  beneath  the 
middle  concha;  and  the  inferior  meatus  beneath  the  inferior  concha- 

^  By  air  is  meant  the  atmospheric  air  by  which  we  are  surrounded.  It  consists 
principally  of  the  two  gases,  oxygen  and  nitrogen,  one  hundred  parts  by  weight  of  air, 
containing  a  little  more  than  twenty  of  oxygen  (20.81)  and  a  little  less  than  eighty  of 
nitrogen  (79.19).     It  is  the  oxygen  which  is  the  essential  part  of  inspired  air. 


THE    RESPIRATORY    ORGANS   AND    RESPIRATION. 


203 


The  nasal  cavities  and  all  of  the  sinuses  which  communicate 
with  them  are  lined  with  mucous  membrane,  which  prevents  the 
drying  effect  of  the  air  upon  the  passages,  tends  to  arrest  foreign 
particles,  and  moderates  the  temperature  of  the  air  on  its  way  to 
the  lungs. 


Fig.   147. — Nasal  Cavity  and  Naso-pharynx  (From  Deaver's  Surgical  Anatomy). 

b,  Superior  turbinal;  a,  superior  meatus;  c,  middle  turbinal;  s,  middle  meatus;  d, 
inferior  turbinal;  e,  inferior  meatus;  g,  i,  j,  tongue;  k,  hyoid  bone;  p,  q,  r,  sphenoid 
l>one  and  sphenoidal  sinus;  t,  naso-pharjmx;  v,  hard  palate  (floor  of  nose). 

The  remaining  references  are  explained  in  another  chapter  (p.  126). 


The  Pharynx. 


The  pharynx  is  the  space  behind  the  nose,  mouth,  and  larynx. 
Its  use  is  to  transmit  a'r  from  the  nose,  and  food  from  the  mouth. 
As  an  air-passage  it  is  included  with  the  respiratory  organs.  (The 
air  passes  from  the  nose  through  the  pharynx  to  the  larynx.) 


204 


ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 


The  Larynx. 

The  larynx  is  situated  below  the  hyoid  bone,  in  front  of  the 
pharynx,  and  projects  slightly  forward  in  the  neck.  It  is  con- 
structed of  fibro-cartilages  connected  with  each  other  by  ligaments 
and  lined  by  mucous  membrane.  The 
largest  fibro-cartilage  is  the  thyroid,  which 
forms  the  prominence  of  the  larynx  known  as 
"Adam's  apple."  Below  the  thyroid  is  the 
cricoid  cartilage,  shaped  like  a  seal  ring, 
and  placed  with  the  broad  part  at  the  back, 
where  two  small  pyramid-shaped  cartilages 
rest  upon  it;  they  are  the  arytenoids.  These 
are  all  connected  by  gliding  joints.  (Other 
cartilages,  very  minute,  are  not  men- 
tioned.) 

The  epiglottis  is  a  leaf-shaped  flexible 
cartilage  extending  upward  from  the  thyroid 
in  front,  and  resting  against  the  base  of  the 
tongue.  During  swallowing  this  is  bent 
backward  over  the  entrance  of  the  larynx 
by  the  action  of  small  muscles,  to  allow  the 
food  to  pass  over  it  into  the  esophagus. 
(For  the  Larynx,  the  Organ  of  the  Voice,  see  page  281.) 


Fig.  148. — Interior  of 
Larynx  (Left  Side  Re- 
moved). 

2,  Epiglottis;  5,  so-called 
"false  vocal  cord";  9,  vocal 
band;  13,  thyroid  cartilage; 
14,  arytenoid  cartilage.  The 
other  figures  refer  to  parts 
not  mentioned  in  the  text. 


The  Trachea. 

The  trachea  is  a  flexible  tube  about  one  inch  in  diameter  and 
four  and  one-half-inches  long,  extending  downward  from  the 
larynx  to  the  level  of  the  fourth  thoracic  vertebra.  It  is  fibrous 
and  elastic,  and  stiffened  with  rings  of  cartilage  which  are  incom- 
plete at  the  back;  unstriped  muscle  fibers  take  their  place,  consti- 
tuting the  tracheal  muscle. 

The  tracheal  muscle  by  the  action  of  its  fibers,  varies  the  size  of  the  trachea 
and  makes  the  tube  soft  where  the  esophagus  lies  next  to  it. 

The  trachea  divides  into  two  branches  called  bronchi.  The  right 
bronchus  is  one  inch  long;  the  left  is  two  inches  long.  (It  passes 
under  the  arch  of  the  aorta.) 

The  bronchi  divide  into  branches  called  bronchial  tubes  which 
subdivide  again  and  again  until  the  smallest  tubes,  called  bronchioles^ 


THE    BRONCmAL    TUBES. 


205 


are  formed.     These  lead  to  the  spaces  called  alveoli,  and  the  air  cells 
clustered  about  them.  ■• 

The  bronchi  and  larger  bronchial  tubes  are  like  the  trachea  in  structure,  con- 
sisting of  fibrous  and  elastic  tissue  with  incomplete  rings  of  cartilage.  In  the 
smaller  tubes  the  rings  become  irregular  plates  or  discs,  and  in  the  bronchioles 
the  cartilage  is  absent  altogether.  The  walls  are  here  very  thin  and  contain 
circular  muscle  fibers  (non-striated),  the  bronchial  muscle. 


;,  v|pjfi%\  Thyroid  cartilage 


Cricoid  cartilage 


Left  bronchus 


Fig.  149. — Larynx,  Trachea,  axd  Bronxhi  (Morris,  modified  from  Bourger>-). 

The  entire  tract  from  the  trachea  down  to  the  air  cells  is  lined 
with  mucous  membrane,  bearing  ciliated  epithelium  as  far  as  the 
smallest  tubes. 

The  cilia  of  the  air  passages  are  fine  hair-like  projections  from  the  surface; 
they  have  a  waving  motion. 

The  Lungs. 

The  lungs  are  two  in  number,  right  and  left,  situated  in  the 
right  and  left  sides  of  the  thorax,  occupying  the  space  enclosed 
by  the  ribs  (not  that  portion  between  the  sternum  and  the  spinal 


2o6 


ANATOMY   AND    PHYSIOLOGY    FOR   NURSES. 


column).     They   resemble   a    flattened   cone   in    shape,    the   apex 
extenduig  one  inch  above  the  clavicle,  the  base  resting  upon  the 

diaphragm.  The  right  lung  is  broader 
and  shorter  than  the  other,  but  it  has 
three  lobes,  upper,  middle,  and  lower.  The 
left  lung  has  two  lobes. 

Note. — The  left  lung  is  narrower 
than  the  right  and  does  not  cover  the 
apex  of  the  heart,  otherwise  it  would  be 
exposed  to  the  motion  of  the  "heart 
beat." 

The    lung    substance     consists    of 
branches  of  the  bronchi  and  their  divi- 
sions down  to  the  bronchioles,  and  the 
Fig.   150.— Clusters  of  Am-    spaces  terminating  in  air-cells.      These 

CELLS  (Holden,  from  KoUiker) .        '■ 

structures  are  surrounded  by  blood-ves- 
sels, nerves,  and  lymphatics,  grouped  together  in  lobules,  supported 
by  fine  fibro -elastic  connective  tissue  and  wrapped  in  pleura. 

Each  bronchiole  terminates  in  a  lobule  (Fig.  150). 

The  root  of  the  lung 
is  composed  of  the  large 
bronchial  tubes,  blood- 
vessels, and  nerves  (see 
illustration  (Fig.  151). 


The  bronchial  tubes  are 
the  primary  divisions  of  the 
bronchi;  the  blood-vessels  are 
— first,  the  bronchial  arteries 
for  the  nutrition  of  the  lung 
substance;  second,  the  pul- 
monary arteries  which  form  a 
fine  network  of  capillaries 
around  the  air-cells,  third, 
the  bronchial  and  pulmonary 
veins. 


Fig. 


:;i. — The  Lungs  utth  Hear:i 
Between  Them. 


The  Pleura. 

Each  lung  is  covered  (except  at  the  root)  by  a  thin  transparent 
sac  of  serous  membrane  called  the  pleura.     One  side  of  this  sac  is 


THE    PLEURA. 


207 


closely  applied  to  the  lung,  forming  the  pulmonary  pleura;  the  other 
side  fits  as  closely  to  the  ribs,  forming  the  costal  pleura.  Within  the 
sac  is  a  small  quantity  of  serous  fluid  (secreted  by  the  endothelium 
of  the  pleura) ,  which  prevents  friction  when  the  ribs  move  and  the 
lungs  expand  or  contract. 

Although  the  hony  thorax  is  bounded  above  by  the  first  rib,  the 
thoracic  cavity  extends  an  inch  above  the  rib  on  each  side,  bounded 
by  an  expansion  of  the  costal  pleura  and  lodging  the  apsx  of  the  lung. 


R.  mammary 

artery 


R.  phrenic  nerve 


Fig.  152. — The  Pleural  Sacs. 
The  dotted  lines  indicate  the  pleural  sacs,  with  space  between  the  layers  (Holden). 

Clinical  note. — If  the  pleura  becomes  inflamed  the  quantity  of  fluid 
diminishes  and  the  surfaces  rub  together,  causing  acute  pain  and  a  fine  crackling 
sound  as  of  friction.     This  condition  is  pleurisy  (or  pleuritis). 

Resume. — In  respiration,  or  the  act  of  breathing,  the  inspired  air 
enters  the  nasal  chambers,  passes  through  the  naso-pharynx,  oro- 
pharynx, larynx,  trachea,  bronchi,  bronchial  tubes,  and  bronchioles, 
to  the  aveoli  and  air-cells  or  air  vesicles. 


THE  PHYSIOLOGY  OF  THE  RESPIRATORY  PROCESS. 

The  function  of  the  respiratory  apparatus  is  first,  to  accomplish 
an  interchange  in  the  lungs,  between  the  oxygen  of  the  air  and  carbon 
dioxide  of  the  blood,  in  other  words — to  bring  nutriment  to  the  blood 
and  to  remove  waste  from  it. 


2o8  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

We  have  seen  how  the  blood  returns  from  the  digestive  organs 
laden  with  food  which  is  to  be  distributed  throughout  the  body, 
and  that  these  products  of  digestion  are  made  over  in  the  tissues  by  a 
process  of  oxidation.  The  source  of  the  oxygen  for  this  process,  is 
the  air  we  breathe.  It  passes  through  the  air  vesicles  and  the 
capillary  walls  into  the  blood,  thence  into  the  lymph  spaces  and 
tissue  cells,  the  tissue  products  returning  (through  the  spaces  and 
the  vessel  walls)  to  the  blood. 

Thus,  the  gas  called  carbon  dioxide  (resulting  from  tissue  action) 
is  brought  by  the  blood  to  the  lungs;  passing  through  the  capillary 
walls  and  the  air  vesicles,  it  is  exhaled  in  the  breath  and  thus  removed 
from  the  body.  Consequently,  respiration  is  a  process  not  only  of 
nutrition  but  of  elimination  as  well. 

This  interchange  is  accomplished  in  part  by  the  physical  process  of  diffusion 
of  gases.  (The  epithelium  of  the  air  vesicles  may  have  a  special  function  to 
this  end,  and  is  called  respiratory  epithelium.) 

By  inspiration  we  take  air,  with  its  oxygen,  into  the  lungs;  by 
expiration  we  expel  it  with  carbon  dioxide,  small  quantities  of  ammonia 
and  organic  waste  matter,  and  moisture. 

This  important  process  is  made  possible  by  the  movements  of 
the  thorax  as  follows: 

In  inspiration. — The  external  intercostal  muscles  elevate  the 
ribs  and  spread  them  apart,  increasing  the  width  of  the  chest ;^ 
the  diaphragm  contracts,  pulling  down  its  central  tendon  and  thus 
increasing  the  depth  of  the  chest;  the  lungs  expand  and  receive  the 
in-drawn  air. 

In  expiration. — The  ribs  fall  easily  back  into  place,  assisted 
by  internal  intercostals  and  abdominal  muscles;  the  diaphragm 
relaxes,  returning  to  its  dome  shape,  and  the  air  is  pressed  out. 

These  acts  are  performed,  in  health,  with  regularity,  that  is,  rhyth- 
mically. The  number  of  respirations  in  a  moment  varies  from 
about  40  in  the  newly  born  to  18  in  the  adult.  Normal  respiration 
is  slowest  when  one  is  lying  down  or  when  sleeping.  The  rate  is 
increased  during  physical  exercise  or  by  emotion,  and  in  visceral 
inflammations,  as  pneumonia,  pleurisy,  peritonitis,  etc.,  also  in 
fevers  generally. 

'  The  Pectoralis  Major  and  some  others  assist  in  deep  breathing  or  forced 
inspiration. 


PHYSIOLOGY    OF    RESPIRATION.  209 

Average  respiratory  rate  at  dijBferent  ages: 

At  one  year 30 

"  six  years 25 

"  twelve  years    20 

Soon  after  this  age,  the  normal  proportion  between  the  number 
of  respirations  and  the  pulse  rate,  is  as  one  to  four. 

The  normal  respiratory  sound  has  been  well  compared  to  the 
rustling  of  leaves  when  the  gentlest  of  breezes  is  blowing  through 
them. 

The  tissues  which  are  most  active  require  most  oxygen.  Con- 
sequently we  can  create  a  demand  and  obtain  a  supply  by  volun- 
tary muscle  exercise  in  good  air,  thus  feeding  the  blood  and  through 
it  the  whole  body,  with  this  most  important  element  of  food. 

Respiration  contributory  to  body  heat  by  providing  oxygen 
for  tissue  change. 

Of  all  organs  the  muscles  are  most  constantly  at  work;  they  can 
dispose  of  more  oxygen  than  any  other  part  of  the  body.  By 
rapid  oxidation  they  generate  more  heat,  but  only  so  long  as  the 
respiratory  organs  keep  pace  with  the  demand  for  rapid  breathing. 

It  is  natural  to  breathe  more  rapidly  as  well  as  more  deeply  on 
a  cold  day,  because  a  low  temperature  of  the  surrounding  air  stimu- 
lates (reflexly)  the  various  activities  of  the  body  to  meet  the  call  for 
warmth,  and  the  respiratory  process  must  be  among  the  first  to 
respond. 

Summary. — Respirationis  a.  nutritive  process, a.neliminative  proc- 
ess and  a  contributing  source  of  body  heat. 

Special  Modifications  of  Respiratory  Movements. 

Rapid  breathing  is  called  hyperpnea. 

Temporary  cessation  of  breathing  is  called  apnea. 

Labored  breathing,  is  dyspnea. 

Dyspnea  follows  any  interference  with  the  interchange  of  gases 
in  the  lungs.  It  may  be  caused  by  diminishing  the  entrance  of 
oxygen,  or  by  increasing  the  CO  2-  It  is  usually  due  to  imperfect 
circulation  in  the  pulmonary  vessels. 

Asphyxia   is    the    condition  resulting  from  a  complete  cutting 
off  of  oxygen  or  an  excessive  increase  of  carbon  dioxide.     It  may  be 
sudden  or  gradual,  but  if  unrelieved,  ends  only  in  death. 
14 


2IO  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

The  change  of  color  noted  in  the  face  of  one  suffering  from, 
dyspnea  and  still  more  from  asphyxia,  is  due  to  the  accumulation 
of  cabon  dioxide  in  the  blood. 

The  importance  of  fresh  air  in  sufficient  quantity  cannot  be 
over-estimated.  One  thousand  cubic  feet  of  space  for  each  adult, 
(equal  to  a  room  lo  feet  in  height,  length  and  breadth)  renewed 
about  three  times  hourly,  is  not  too  much. 


CHAPTER  XIV. 


THE  KIDNEYS.     THE  SKIN.     ELIMINATION. 


The  kidneys  (renes)  are  organs  of  excretion;  that  is,  they  separate 
certain  waste  matters  from  the  blood,  in  a  definite  form  for  removal 
from  the  body. 

They  are  situated  for  the  most  part  in  the  posterior  lumbar  region, 
just  in  front  of  the  quadratus  lumborum  muscles,  extending  from 


Left  kidney 


Right  urettr 


Left  ureter 


Fig.  153. — The  Kidxeys  (Morris). 

about  the  tenth  rib  to  within  two  or  three  inches  from  the  crest  of 
the  ilium.  They  are  shaped  like  a  bean,  about  four  or  five  inches 
long  and  one  and  one-half  inches  wide,  with  the  concave  border,  or 
hilus,  turned  toward  the  spinal  column;  and  they  arc  imbedded  in 
fat  behind  the  peritoneum. 

The  kidney  is  hollow,  the  cavity  within  being  called  the  sinus. 
It  is  covered  by  a  fibrous  capsule  which  also  lines  the  sinus. 


212 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


Structure. — A  kidney  is  a  mass  of  minute  tubes,  the  uriniferoiis 
tubules.     At   the   beginning   of    each   is   a   bulb-Hke   enlargement, 

indented  to  form  a  deep 
hollow  (Bowman's  capsule, 
Fig.  154)  which  encloses  a 
tuft  of  renal  blood-vessels. 
The  capsule  and  vessels 
together  constitute  a  Mal- 
pighian  or  renal  corpuscle. 
As  the  tubule  leaves  the 
bulb  it  twists  and  turns 
many  times  and  is  called 
the  convoluted  tubule.  It 
has  a  network  of  blood- 
vessels around  it.  The 
convoluted  tube  finally  be- 
comes straight,  and  at  last 
several  straight  ones  unite 


Fig.   154. — -Scheme  of  the  Renal  or 
Malpighian  Corpuscle. 

I.  Interlobular  artery.  2.  Afferent  vessel. 
3 .  Efferent  vessel.  4.  O  uter  wall.  5.  Inner  wall. 
6.  Glomerulus.     7.  Neck  of  tubule  (Stohr). 


to    form    a    collecting   tube 
which  opens  into  the  sinus. 

Malpighian  corpuscles  and  convoluted  tubes  occupy  most  of  the 
portion  of  the  kidney  near  the  surface,  forming  the  cortex  (or  cortical 
portion) .  The  straight  or  collecting  tubes  are 
grouped  together  into  pyramids,  pointing 
toward  the  interior  and  forming  the  medullary 
portion.  The  apex  of  each  pyramid  projects 
into  the  sinus,  presenting  the  openings  of 
several  collecting  tubes  (Fig.  155). 

The  cells  which  line  this  system  of  tubes 
do  the  work  of  excreting  the  urine  from  sub- 
stances in  the  blood,  thus  relieving  it  of 
poisonous  elements  which  would  surely  cause 
death  if  allowed  to  remain. 

The  urine  is  conducted  from  the  kidney 
to  the  bladder  through  the  ureter,  a  slender 
musculo-fibrous  duct  about  twelve  inches 
long,  the  upper  end  of  which  is  enlarged  and  called  the  pelvis  of  the 
kidney.  (It  occupies  the  sinus.)  It  has  a  thin  layer  of  muscle 
fibers  and   is   lined  with  mucous   membrane.      The   two  ureters 


Fig.  155. — Section  os 
Kidney  (Potter). 


PHYSIOLOGY    OF    THE    KIDNEYS.  213 

extend  into  the  true  pelvis  to  the  base  of  the  bladder,  where  they 
terminate  about  one  inch  apart.  (The  course  of  the  ureter  is 
further  described  on  page  283  with  the  description  of  the  bladder.) 

Clinical  notes. — The  amount  of  urine  excreted  by  a  person  varies  greatly, 
but  in  health  averages  48  ounces  or  3  pints  daily;  it  is  directly  affected  by  the 
quantity  of  fluid  which  the  person  drinks  and  the  amount  of  perspiration 
formed. 

Renal  colic  is  caused  by  the  attempt  to  pass  a  small  stone,  or  calculus,  through 
the  ureter. 

PHYSIOLOGY  OF  THE  KIDNEYS. 

This  is  to  remove  waste  matters  from  the  blood  in  the  form  of  an 
excretion  called  urine.  Urine  is  a  watery  fluid  of  amber  color, 
somewhat  heavier  than  water  (1010-1020),  with  a  characteristic 
odor,  and  having  the  temperature  of  the  body  at  the  time  of  voiding. 
Its  reaction  is  normally  acid. 

The  coloring  matter  is  derived  from  bile  pigments;  it  is  deep  or 
pale,  as  the  urine  contains  less  or  more  water.  The  weight  is  due  to 
the  salts  contained,  both  organic  and  inorganic  (or  mineral)  and 
this  also  is  modified  by  the  amount  of  water.  Both  water  and  salts 
vary  markedly  with  the  dietary  of  the  indi\ddual. 

Clinical  notes. — The  color  and  odor  may  both  be  modified  by  drugs  or  by 
articles  of  food.  (For  example,  turpentine  causes  the  odor  of  violets,  vi'hile 
that  imparted  by  asparagus  is  well  known.)  Urine  containing  blood  cells  is 
smoky  in  appearance;  and  every  nurse  knows  what  methylene  blue  will  do. 

The  most  important  substance  to  be  excreted  in  the  urine  is  urea. 
This  represents  the  absolutely  useless  material  remaining  from 
proteid  foods.  It  is  prepared  for  excretion  in  the  liver.  It  is  the 
substance  which  if  allowed  to  accumulate  in  the  system  becomes  a 
deadly  poison,  causing  death  by  uremia. 

Uric  acid  is  proteid  waste  in  another  form  and  smaller  quantity. 
Phosphates  of  sodium,  potassium  and  calcium  are  present  normally, 
also  other  mineral  salts,  sodium  chloride  (common  salt)  being  the 
most  abundant. 

Water  is  necessary  for  the  solution  of  all  these  solids  (they  would 
be  solid  without  water).  This  varies  in  quantity  in  many  systemic 
conditions.  Increased  activity  of  the  lungs  and  skin,  for  example, 
removes  water  from  the  blood  and  leaves  the  urine  more  dense. 
Fevers  arc  always  accompanied  by  a  decrease  in  the  quantity.     It 


214  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

may  be  increased  by  nervous  excitement;  nervous  urine  is  pale  and 
thin,  since  it  is  the  water  which  is  increased. 
Suppression  of  urine  means  inability  of  the  kidney  to  act. 

The  process  of  excretion  in  the  kidney  is  one  of  filtration  and  secretion.  The 
kidney  has  a  large  blood  supply  through  the  renal  artery,  which  enters  at  the 
hilum  and  divides  at  once  into  several  branches.  The  capillaries  from  these 
arteries  are  very  numerous.  They  enter  first  the  capsule  of  the  Malpighian 
body  {afferent  vessels)  and  form  a  cluster  or  tuft  there,  from  which  the  water  and 
salts  are  filtered  out  and  pass  into  the  tubule.  They  then  leave  the  capsule 
{efferent  vessels)  and  twist  themselves  about  the  convoluted  tubules,  whose 
epithelial  cells  select  the  organic  substances — urea,  iiric  acid  and  others.  These 
are  washed  down  by  the  watery  solution  coming  from  the  capsule,  to  the  apices 
of  the  pyramids  and  there  discharged  into  the  pelvis  of  the  kidney,  as  urine. 

The  ureter  conducts  the  urine  from  the  kidney  to  the  urinary 
bladder,  where  in  due  time  it  is  expelled  through  the  urethra.  The 
act  of  expelling  the  urine  is  micturition  (clinically  we  often  speak  of 
it  as  urination).  The  bladder  walls  contract,  the  sphincter  of  the 
urethra  relaxes,  and  the  urine  escapes. 

If  the  bladder  is  not  able  to  expel  its  contents  we  say  the  patient 
has  retention  of  urine.  This  inability  may  be  so  complete  that  the 
bladder  becomes  entirely  filled  and  the  sphincter  can  no  longer  act; 
the  urine  dribbles  away  and  the  condition  is  one  of  "retention  with 
overflow"  from  inability  of  the  bladder  to  contract. 

THE  SKIN. 

The  skin,  or  integument,  is  the  elastic  and  protective  covering  of 
the  body.  It  consists  of  two  layers,  a  deep  one  called  the  corium, 
and  a  superficial  one  called  the  epidermis. 

The  corium  or  "true  skin"  {cutis  vera)  is  a  vascular,  elastic  and 
sensitive  layer,  red  and  soft;  resting  upon  a  loose  subcutaneous 
tissue.  Its  deep  portion  is  well  supplied  with  vessels  and  nerves 
{tactile  cells)  supported  by  a  fibrous  and  elastic  network  (reticular 
layer)  which  contains  non-striated  muscle  fibers  and  fat.  In  this 
layer  are  the  blood-vessels,  nerves  and  lymphatics. 

Tiny  projections  called  papillce  rise  from  this  network  portion, 
each  papilla  containing  a  special  nerve-ending  called  a  touch  cor- 
puscle. They  are  arranged  in  rows  forming  ridges  which  are  cir- 
cular on  the  front  of  the  finger  tips.     It  is  a  remarkable  fact  that 


THE    SKIN. 


215 


no  two  fingers  or  toes  are  alike  in  this  respect,  hence  the  thumb- 
or  finger-mark  is   a   means   of  identification. 

The  papillae  constitute  a  "papillary  layer."     There  are  still  other  nerve 
endings  in  the  corium  for  different  sensations. 

The  epidermis  (or  cuticle)  completely  covers  the  corium.  It  con- 
sists of  layers  of  cells  of  varying  character  and  thickness.  The 
deeper  cells  are  soft  and 
nucleated,  but  near  the 
surface  they  become  flat 
and  dry,  until  finally  they 
are  mere  tiny  scales. 

The  epidermis  has  no 
vessels  and  scarcely  any 
nerves,  consequently  it  is 
not  sensitive  and  does 
not  bleed. 

The  deep  layers  of 
the  epidermis  contain  the 
coloring  matter  or  pig- 
ment of  the  skin,  which 
comes  away  with  a  blis- 
ter. The  pigment  varies 
in  different  people  and 
races.  Exposure  to  heat 
and  sun  deepens  it. 


Fig.  156. 
Showing  the  layer.s  of  the  skin  (greatly  magnified) , 
with  the  sweat  glands  and  oil  glands,  and  a  hair  in 
its  follicle  (Brubaker). 


Clinical  notes. — The 
insensitive  and  bloodless 
character  of  the  epidermis 
or  cuticle  are  plainly  demon- 
strated in  the  dressing  of  a  blister,  when  it  is  incised  to  allow  the  escape  of 
serum  which  has  accumulated  between  it  and  the  corium  or  true  skin. 

The  surface  of  the  epidermis  is  continually  wearing  away  and  new  layers  of 
epithelial  cells  are  exposed,  to  become  dry  and  scaly,  and  to  be  shed  in  their  turn. 
It  varies  in  thickne.ss  according  to  the  degree  of  friction,  or  pressure,  or  exposure 
which  it  encounters.     Witness  the  palms  of  the  hands,  and  the  soles  of  the  feet. 

The  elasticity  of  the  skin  is  demonstrated  when  a  cut  is  made 
through  the  corium.  The  edges  retract  and  some  effort  is  required 
to  bring  them  together  again.     The  elasticity  is  due  not  only  to  the 


2l6  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

elastic  fibers  in  the  deep  layer  of  the  cerium,  but  to  the  muscle  fibers, 
small  though  they  be. 

The  glands  of  the  skin  are  in  the  corium;  their  ducts  pass 
through  the  epidermis  to  open  upon  the  surface.  They  are  of  two 
kinds — the  sebaceous  glands  and  the  sweat  glands  {sudoriferous  glands) . 

The  sebaceous  glands  are  found  in  the  skin  of  all  parts  of  the 
body  except  the  palms  and  soles.  They  are  most  numerous  upon 
the  face.  They  produce  an  oily  substance  called  sebum  which 
renders  the  skin  soft  and  pliable.  Their  ducts  open  into  the  depres- 
sions (follicles)  for  the  roots  of  hairs,  consequently  they  preserve 
the  softness  and  glossiness  of  the  hair. 

Ear  wax,  or  cerumen,  is  secreted  by  specialized  glands  in  the 
auditory  canal. 

Note.^ — ^The  vernix  caseosa  which  is  found  upon  the  skin  of  the 
new-born  child  is  an  accumulation  of  sebaceous  matter  which  has 
served  to  protect  the  skin  from  the  effect  of  long  submersion  in  the 
amniotic  fluid. 

The  sweat  glands  (sudoriferous  glands)  are  found  in  the  skin  of 
the  entire  body.  Each  gland  consists  of  a  coiled  tube  embedded  in 
the  corium,  with  a  duct  opening  upon  the  surface;  these  ducts  open 
upon  the  ridges  made  by  the  rows  of  papillae.  With  an  ordinary 
magnifying  glass  the  droplets  of  sweat  may  be  seen. 

The  sweat  or  perspiration  is  a  thin  watery  fluid  (highly  acid,  but 
saline  to  the  taste),  containing  a  number  of  substances  in  solution, 
derived  from  the  vessels  in  the  network  of  the  corium.  The  most 
important  are  salt,  phosphates,  urea  and  carbon  dioxide. 

It  is  estimated  that  the  2,000,000  or  more  glands  secrete  nearly  a  liter  of 
perspiration  daily,  in  health.  The  process  goes  on  continually;  when  the 
rate  of  excretion  is  moderate  and  uniform  we  are  not  aware  of  it,  because  the 
moisture  is  removed  in  various  ways  as  soon  as  formed — this  is  insensible  per- 
spiration. When  the  removal  does  not  keep  pace  with  the  production,  the 
accumulation  on  the  skin  becomes  sensible  perspiration. 

The  appendages  of  the  skin  are  the  glands  already  described, 
the  nails  and  the  hairs. 

The  nails  belong  to  the  cuticle  (being  modifications  of  its  epi- 
thelium). They  give  protection  to,  and  add  power  and  ease  in 
using  the  digits.  They  lie  upon  a  bed  of  corium  called  the  matrix, 
from  which  they  grow;  if  the  matrix  be  destroyed  the  nail  is  lost  and 
no  new  one  will  grow  in  its  place.     The  root  of  the  nail  is  embedded 


PHYSIOLOGY    OF    THE    SKIN.  21'J 

in  a  fold  of  skin;  the  white  semicircle  at  the  root  is  called  the  lunula 
(little  moon). 

The  hairs  also  belong  to  the  cuticle.  They  are  distributed 
over  the  greater  part  of  the  surface  of  the  body,  being  conspicuous 
on  the  scalp. 

A  hair  consists  of  a  root  and  a  shaft.  The  root  rests  upon  a 
minute  papilla  in  the  bottom  of  a  depression  or  hair  follicle.  The 
nerves  and  blood-vessels  do  not  run  beyond  the  papilla. 

The  shaft  extends  outward  from  the  root,  and  contains  the  pig- 
ment which  decides  the  color  of  the  hair. 

The  hairs  lie  obliquely  on  the  skin  but  may  be  made  to  stand 
erect  by  the  contraction  of  a  tiny  muscle  bundle  placed  at  the  root  of 
each  one.  These  are  the  erectors  of  the  hairs.  It  is  their  action 
which  gives  the  appearance  called  "goose-flesh."  The  softness  and 
the  gloss  of  hair  are  due  to  the  oil  which  is  poured  into  the  follicles 
by  the  oil  glands. 

Note. — The  fine  hair  on  the  skin  of  the  new-born  child  is  called 
lanugo.  It  begins  to  grow  at  about  the  fifth  month  of  intra-uterine 
life,  and  wears  away  soon  after  birth. 

The  hairs  which  border  the  eyelids  are  called  cilia. 

PHYSIOLOGY  OF  THE  SKIN. 

The  skin  has  a  triple  function.  It  is  the  protective  covering  of  the 
body;  an  organ  of  excretion  and  an  organ  of  the  special  sense  of  touch. 

As  a  protective  it  is  mechanical  only;  the  insensitive  layers 
receiving  first  the  impressions  of  external  forces — heat,  cold,  blows, 
etc.,  diminish  their  effects  on  deeper  and  sensitive  ones. 

As  an  organ  of  touch  it  is  referred  to  on  page  271. 

Its  most  important  function  is  that  of  secreting  perspiration. 
Perspiration  is  a  clear  watery  fluid  consisting  of  a  solution  of  certain 
waste  products  of  metabolism  (tissue  waste),  in  other  words,  water 
and  solids.  It  is  acid  in  reaction;  saline  to  taste.  The  quantity 
excreted  by  a  healthy  active  person  in  twenty-four  hours,  has  been 
estimated  as  one  quart. 

Although  the  amount  of  solids  in  the  perspiration  is  small,  it  is 
enough  to  embarrass  the  system  if  retained,  and  to  relieve  it  if  the 
kidneys  are  disabled.  Urea  is  one  of  the  substances  contained  in 
perspiration,  and  in  diseased  conditions  of  the  kidneys  the  skin  is 
able  to  excrete  an  increased  quantity  of  urea. 


2l8  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

The  removal  of  tissue  waste  is,  however,  not  the  only  important 
use  of  perspiration.  By  bringing  water  to  the  surface  of  the  skin,  it 
is  a  most  efficient  agent  for  regulating  the  temperature  of  the  body. 
Muscle  exercise,  for  example,  which  increases  heat  production,  is 
accompanied  by  increased  activity  of  the  sweat  glands,  and  the 
consequent  evaporation  of  water  carries  off  the  excess  of  heat  gener- 
ated in  the  muscles.  Again,  high  temperature  of  the  surrounding 
atmosphere  causes  dilatation  of  the  cutaneous  vessels,  and  more 
perspiration  and  consequent  evaporation.  Conversely,  a  cold  atmos- 
phere stimulates  the  cutaneous  vessels  to  contract,  and  stops  the 
production  of  sensible  perspiration. 

Clinical  note. — From  these  facts  one  may  understand  why  it  is  so  important 
to  conserve  the  surface  temperature  of  a  patient  with  nephritis,  or  with  diminu- 
tion of  urine  from  any  cause,  by  the  use  of  blankets  and  warm  clothing;  and  to 
increase  it  oftentimes  by  the  use  of  hot  baths,  packs,  etc. 

In  health  the  quantity  of  perspiration  is  modified  by  the  dietary, 
particularly  by  the  amount  of  liquid  taken,  and  the  kind  of  liquid; 
also  by  the  character  of  clothing,  the  season  of  the  year,  etc. 

It  may  be  noted  that  the  activities  of  the  skin  and  kidneys  alter- 
nate with  change  of  season;  in  summer  when  the  skin  is  active  the 
urine  is  scanty.  In  winter,  when  the  skin  is  inactive  the  urine  is 
free. 

In  fevers,  cutaneous  vessels  are  dilated,  but  the  nerve  stimulus 
to  cell  action  is  dulled;  the  effect  of  baths  upon  the  skin  is  to  abstract 
heat,  improve  the  tone  of  cutaneous  structures,  and  favor  the  action 
of  the  glands. 

In  renal  diseases,  activity  of  the  skin  is  to  be  promoted;  in  fevers, 
activity  of  the  kidneys  is  encouraged  as  well  as  of  the  skin. 

Summary. — The  skin  is  protective,  excretory,  an  organ  of  special 
sense  and  of  heat  regulation. 


CHAPTER  XV. 

MAMMARY     GLANDS.       DUCTLESS  GLANDS.       GENERAL 

METABOLISM. 

THE  MAMMARY  GLANDS. 

The  mammary  glands  are  placed  between  two  layers  of  super- 
ficial fascia  in  front  of  the  thorax,  occupying  a  space  between  the 
third  and  sixth  ribs,  inclusive.  They  are  covered  by  a  layer  of  adi- 
pose tissue  and  lie  between  two  layers  of  superficial  fascia.     They 


Acrola 


Fig.  157. 
Showing  enlarged  milk  ducts  during  lactation  (Morris). 

consist  of  little  tubes,  lined  with  milk-secreting  cells  and  grouped 
in  small  lobules,  held  together  by  connective  tissue  imbedded  in 
adipose.  The  lobules  unite  to  form  lobes,  18  or  20,  each  with  its 
own  duct,  consequently  18  or  20  milk  ducts  approach  the  nipple  and 
open  at  its  summit.  The  nipple  is  surrounded  by  a  ring  of  darker 
modified  skin  called  the  areola. 

The  function  of  the  mammary  gland  is  the  secretion  of  milk. 
This  is  a  true  secretion;  the  cells  of  the  tubules  forming  a  new  sub- 

219 


220  ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 

stance  from  materials  brought  by  the  blood,  which,  although  not 
utilized  in  the  body  where  it  is  formed,  is  not  only  useful  but  capable 
of  sustaining  life. 

Milk  is  a  bluish-white  fluid  consisting  of  clear  plasma  {milk 
plasma)  holding  nutritive  substances  in  solution  and  floating  myriads 
of  oil  globules,  to  which  it  owes  its  white  color.  It  is  a  natural 
emulsion.  The  variety  of  nutritive  substances  contained  is  suffi- 
cient for  the  development  of  the  body  of  the  infant. 

The  special  proteid  of  milk  is  caseinogen,  from  which  casein  is  derived  in  the 
process  of  digestion  (see  p.  146).  (Artificial  coagulation  of  milk  separates  the 
casein  and  fat  from  the  plasma,  the  curd  from  the  whey.) 

The  sugar  of  rnilk  is  lactose. 

The  salts  are  the  various  salts  found  in  foods  and  body  tissues. 

During  pregnancy  the  areola  acquires  a  deeper  color,  which  is 
permanent.     (A  secondary  areola  may  form.) 

At  this  time  the  blood  supply  of  the  gland  increases,  the  glands 
become  large,  and  changes  occur  in  the  lining  of  the  tubules,  which 
result  in  the  secretion  of  milk.  This  is  perfected  soon  after  the  end 
of  pregnancy. 

The  first  fluid  which  is  drawn  from  the  breast  is  called  colostrum; 
it  contains  an  excess  of  sugar  and  inorganic  salts,  and  a  substance 
which  acts  as  a  laxative  for  the  infant. 

The  secretion  of  milk  is  influenced  by  the  diet  of  the  mother  and 
may  be  modified  in  both  quantity  and  quality  by  food  selection.  A 
still  greater  effect  is  produced  by  the  condition  of  the  nervous  system; 
it  is  well  known  that  fright  or  anger,  or  intense  emotion,  affect  the 
milk  so  as  to  make  it  injurious  to  the  infant.  Fatigue,  worry,  loss  of 
sleep  etc.,  are  all  to  be  avoided  by  the  nursing  mother. 

Surgical  note. — Mammary  abscess  is  caused  by  infection  through  a  break 
or  fissure  in  the  skin  of  the  nipple,  the  pus  forming  between  the  lobules  of  the 
gland.     Post-mammary  abscess  is  in  the  fascia  behind  the  gland. 

THE  DUCTLESS  GLANDS. 

These  are  the  organs  which  resemble  glands  but  have  no  ducts. 
They  are  supplied  with  sympathetic  nerves,  and  possess  many 
lymphatics  and  blood-vessels;  the  secretions  which  they  produce 
are  carried  in  these  vessels.  The  most  important  ductless  glands 
are  the  spleen,  adrenal  bodies  and  pancreas  in  the  abdomen;  thyroid, 
parathyroid,  and  thymus  bodies  in  the  neck. 


SPLEEN.       PANCREAS.  221 


The  Spleen. 


The  spleen  (or  lien)  is  situated  at  the  left  of  the  stomach, 
directly  beneath  the  diaphragm  by  which  it  is  entirely  covered.  It 
is  oval  in  shape,  convex  on  the  lateral  surface  and  concave  on  the 
medial,  where  a  depression  called  the  hilus  is  seen  for  the  passage  of 
vessels  and  nerves  (Fig.  104.  p.  133). 

The  fibromuscular  capsule  which  forms  the  surface  of  the  spleen 
sends  numerous  septa  into  the  interior,  and  within  the  spaces  of  the 
network  thus  formed  the  splenic  pulp  is  contained.  This  consists  of 
blood  which  has  escaped  from  the  open  terminals  of  numberless 
capillaries,  of  lymphoid  cells  and  broken  down  red  cells,  coloring 
matter  and  particles  of  waste. 

Small  collections  of  lymphoid  cells  around  the  capillaries  may  be 
seen  upon  section  of  the  organ;  they  are  the  Malpighian  bodies  of  the 
spleen;  their  function  is  obscure. 

The  splenic  artery  is  the  largest  branch  of  the  celiac  axis  and  the 
consequent  large  blood  supply  gives  a  dark  red  color  to  the  spleen. 
The  peritoneal  covering  completely  surrounds  it,  except  to  allow 
vessels  and  nerves  to  pass  through  the  hilus. 

The  function  of  the  spleen  is  not  well  understood,  as  both 
animals  and  human  beings  have  been  known  to  live  in  health  after 
its  removal,  but  from  its  structure  and  the  results  of  examinations  of 
blood  from  both  the  splenic  artery  and  splenic  vein,  it  is  thought 
that  white  cells  are  there  added  to  the  blood,  and  worn-out  red 
cells  are  destroyed. 

Clinical  notes.— The  elasticity  of  the  capsule  allows  frequent  variations  in 
size,  which  in  health  are  normal;  it  is  always  larger  during  digestion  and  smaller 
in  fasting.  In  certain  diseased  conditions  it  is  much  increased  in  size,  as  in 
malaria;  and  notably  in  leukemia,  which  is  characterized  by  an  enormous 
increase  in  the  number  of  white  cells  in  the  blood,  as  w^ll  as  in  the  size  of  the 
organ  itself. 

The  Pancreas. 

In  addition  to  the  digestive  ferments  of  the  pancreas  it  would 
seem  that  it  produces  another  substance,  which  either  disposes  of 
sugar  in  the  blood,  or  is  associated  with  the  glycogenic  function  of 
the  liver,  or  both.     This  is  supposed  to  be  the  special  function^  of 

I  Now  disputed 


222 


ANATOMY  ANY    PHYSIOLOGY    FOR    NURSES. 


groups  of  cells  called  "islands  of  Langerhans"  which  are  embedded 
in  the  substance  of  the  pancreas.  They  resemble  glands  but  have 
no  ducts;  they  are  surrounded  by  a  network  of  capillaries  and  their 
internal  secretion  is  probably  transmitted  by  these  vessels. 

The  blood  supply  to  the  pancreas  is  very  free,  being  derived  from 
the  hepatic,  splenic  and  superior  mesenteric  arteries.  This  indicates 
the  importance  of  the  gland  (Figs.  104,  105). 

The  Adrenal  Bodies. 

The  adrenals  {suprarenal  capsules),  are  two  small  gland-like 
bodies  resting  on  the  upper  extremities  of  the  kidneys,  hence  their 
name.  They  are  triangular  in  shape,  yellowish  in  color,  and  have 
many  blood-vessels  and  nerves.  They  are  important  organs,  as  it 
is  found  that  when  they  are  removed  death  follows  soon,  but  their 
use  is  not  yet  fully  understood.  It  has, 
however,  been  determined  that  their  internal 
secretions,  adrenalin,  epinephrin,  stimulate  the 
muscles  of  the  heart  and  arteries,  thus  in- 
creasing blood  pressure.  In  the  disease 
called  "bronzing  of  the  skin,"  or  Addison's 
disease,  these  bodies  are  found  to  be  changed. 

The  Thyroid  Body. 


The  thyroid  body  is  situated  in  the  an- 
terior part  of  the  neck.  It  has  two  lateral 
lobes  lying  close  to  the  trachea  and  connected 
by  a  middle  portion  called  the  isthmus. 
These  lobes  are  about  one  and  one-fourth 
inches  wide,  and  extend  about  two  inches 
upward  along  the  sides  of  the  larynx. 

The  substance  of  the  thyroid  body  is  made  up  of  closed  sacs  con- 
taining a  thick  semifluid  substance  {colloid  substance).  They  are 
surrounded  by  many  capillaries ;  the  thyroid  arteries  being  four  in 
number,  the  blood  supply  is  very  free. 

The  function  of  the  thyroid  body  is  important  but  not  well  ex- 
plained. It  is  observed  that  the  development  of  both  mind  and 
body  is  arrested  if  the  thyroid  be  absent,  or  if  it  does  not  itself 
develop  in  childhood;  this  condition  is  known  as  cretinism. 

Degeneration  or  complete  removal,  in  adult  life,  is  followed  by 


Fig.  158. — The  Adenal 
Body  is  seen  resting 
UPON  THE  Kidney. 


PARATHYROID   AND    THYMUS    BODIES. 


223 


excessive  growth  (but  imperfect  development)  of  connective  tissue 
and  skin  elements,  or  myxedema. 

From  these  and  other  clinical  observations  it  is  evident  that  the 
internal  secretion  of  this  body  exercises  an  important  influence 
upon  nutrition.  It  also  stimulates  cardiac  action,  and  restrains  a 
tendency  to  obesity. 

Simple  enlargement  of  the  thyroid  body  constitutes  goiter,  which  is  said 
to  be  frequent  in  certain  countries  where  the  drinking  water  contains  much 
lime. 


Median  portion  of  crico- 
thyroid membrane 

Crico-tyroid  muscle 


UTERAL  LOBE  OF  THYROID  BOD» 


THYROID  ISTHMUS 


Fig.  159. — Thyroid  Body  (Morris). 

The  Parathyroid  Bodies. 

The  parathyroid  bodies  are  small  bodies  situated  above  and 
laterally  to  the  thyroid,  two  on  each  side.  They  have  an  abundant 
blood  supply.  Their  function  is  not  explained  but  it  is  now  known 
that  their  removal  is  followed  by  convulsive  affections,  tremor,  etc., 
suggesting  the  presence  of  an  irritant  which  did  not  exist  before. 
Consequently  it  may  be  that  their  internal  secretion  is  capable  of 
destroying  or  perhaps  preventing  the  formation  of  certain  toxic 
substances. 

Both  parathyroid  and  thyroid  bodies  contain  iodin  in  combina- 
tion within  some  other  substance. 


The  Thymus  Body  (Fig.  160). 

The  thymus  body  is  an  organ  of  fetal  and  infantile  life,  situated 
below  the  thyroid,  being  mostly  in  the  thorax  and  reaching  down  to 


224 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


the  pericardium.  It  is  two  and  one-half  inches  long  at  the  age  of 
two  years,  but  dwindles  slowly  from  that  time  on,  leaving  only  some 
shreds  of  tissue  at  the  age  of  fourteen. 

The  Pituitary  Body  (Fig.   179). 

The  pituitary  body  {hypophysis  cerebri)  is  now  included  among 
ductless  glands.  It  rests  in  the  sella  turcica  of  the  sphenoid  bone. 
By  investigation  it  has  been  learned  only  that  degeneration  of  this 


THYROID 


LUNQ. 


LIVER 
Suspensory  ligament 


SMALL  INTESTINE 


BLADDER 


TRACHEA 


LUNG 

RIGHT  AURICLE 


RIGHT  VENTRICLE 


PART  OF  TRANSVERSE 
COLON 


Hypogastric  artery 


Fig.  160. — -Viscera  at  Birth.  Note  the  Thymus  Body,  the  Size  of  the  Liver 
AND  the  Location  of  the  Bladder  and  the  Hypogastric  Arteries  (Morris 
after  Rudinger). 

body  accompanies  the  disease  called  acromegaly,  which  is  charac- 
terized by  an  overgrowth  or  hypertrophy  of  the  bones  of  the  face  and 
extremities. 

Certain  conclusions  have  been  founded  upon  this  association, 
presupposing  that  it  produces  an  internal  secretion  which  regulates 
the  growth  of  bones. 

It  probably  has  some  effect  upon  the  force  of  cardiac  action. 


SECRETIONS.  225 

SECRETION,  ELIMINATION,  HEAT  PRODUCTION. 

We  have  now  studied  the  various  organs  which  form  secretions, 
or  substances  which  may  either  be  devoted  to  a  special  use  in  the 
body,  or  expelled  as  of  no  further  use.  These  latter  are  known  as 
excretions. 

Following,  is  an  enumeration  by  way  of  review,  of  the  principal 
organs  whose  secretions  are  used  in  the  body: 

First. — The  epithelial  cells  of  all  surface  membranes  and  cavities 
should  be  included: 

Those  of  mucous  membranes,  secreting  mucus. 
Those  of  serous  membranes,  secreting  serum  (as  in  the  pleural,  peri- 
cardial and  peritoneal  cavities,  and  the  subdural  and  subarachnoid 
spaces  of  brain  and  spinal  cord). 

Those  of  synovial  membranes,  secreting  synovia. 

The  secreting  cells  of  glands  come  next. 

The  salivary,  gastric  and  intestinal  glands  secrete  saliva,  gastric 
and  intestinal  juices. 

The  liver  secretes  bile  (and  forms  glycogen). 

The  mammary  glands  secrete  milk. 

The  lacrimal  glands  secrete  tears. 

The  sebaceous  glands  secrete  sebum. 
Of  the  secretions  of  so-called  ductless  glands. 

That  of  the  pancreas  favors  glycogen-processes  in  the  liver. 

That  of  the  adrenal  bodies  increases  blood  pressure. 

That  of  the  thyroid  body  influences  tissue  metabolism,  increases 
cardiac  action,  and  diminishes  obesity. 

That  of  the  parathyroids  prevents  or  destroys  toxins  in  the  blood. 

That  of  the  pituitary  body  (or  hypophysis)  restrains  growth  of 
osseous  tissue. 

Th&  spleen  arid  lymph  glands  svi^t^ly -whitQ.  cq[\s  .  .  1       ,,      , 

The  marrow  of  bones  supplies  red  cells / 

The  ovaries  produce  ova. 

The  testes  produce  spermatozoa. 

Thus,  the  secretions  of  the  organs  named,  serve  various  purposes, 
aiding  or  influencing   nutrition   or  assisting   in   the  formation    of 
other  substances. 
IS 


226  ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 

Excretions. — These  are  the  substances  which  must  be  elimi- 
nated from  the  body. 

All  tissue  action  uses  up  some  material,  leaving  a  varying  remnant 
of  waste  matter  which  cannot  be  utilized — like  the  ashes  from  a  fire. 
These  wastes  appear  either  dissolved  in  water  as  urine  and  perspira- 
tion, or  in  the  form  of  gas  or  vapor. 

Tissue  waste  may  be  reduced  ultimately  to  comparatively  few 
substances,  the  most  important  being  urea,  carbon  dioxide,  various 
salts  and  water.  Urea  is  most  abundant  in  urine,  CO  2  in  exhaled 
air,  and  all  of  these  in  small  quantity  in  perspiration. 

Therefore,  the  organs  of  elimination  are: 

The  kidneys,  which  excrete  urine. 

The  skin,  which  excretes  perspiration. 

The  lungs,  which  exhale  carbon  dioxid,  organic  matters,  am- 
monia and  water. 

ANIMAL  HEAT. 

The  cell  activities  described  in  the  preceding  pages,  in  other 
words — the  processes  of  metabolism,  all  generate  heat.  This  is  an 
important  matter,  as  an  internal  temperature  of  about  100°  F.  is 
necessary  to  the  normal  activity  of  the  body  tissues.  This,  the  tissues 
themselves  can  accomplish  with  proper  materials  in  the  form  of 
food,  and  oxygen  for  the  chemical  work,  the  latter  being  supplied  in 
the  air  we  breathe. 

A  slight  rise  of  temperature  normally  accompanies  digestion, 
especially  if  hot  fo.ods  be  taken.  The  kind  of  food  which  is  eaten 
has  a  direct  effect  upon  the  production  of  heat;  proteid  substances 
yield  more  than  starchy  foods,  while  fats  yield  more  than  proteids 
and  starches  together. 

As  the  body  is  continually  generating  heat  so  it  is  continually 
losing  it  in  various  ways — to  the  surrounding  atmosphere  by  radi- 
ation, to  clothing  by  conduction,  by  evaporation  from  the  lungs  and 
the  skin,  etc.,  etc. 

In  cold  weather  heat  production  is  desired.  This  can  be  accom- 
plished by  selecting  heat-generating  foods,  by  taking  hot  foods  and 
by  muscle  exercise;  the  heat  thus  generated  can  be  conserved  by 
clothing  the  body  in  materials  which  prevent  radiation  and  con- 
duction, as  wool  or  silk.     In  hot  weather  heat  production  is  to  be 


THE    BODY    HEAT.  227 

avoided  and  heat  dissipation  is  sought;  this  is  facilitated  by  the 
selection  of  starchy  and  proteid  foods,  taking  cool  drinks  and  wear- 
ing lighter  garments,  as  cotton  or  linen. 

For  health  and  comfort  it  is  necessary  that  a  proper  relation  be 
maintained  between  heat  production  and  heat  dissipation.  For 
this,  the  body  possesses  its  own  self-regulating  mechanisms;  for 
example,  muscle  exercise  produces  heat,  but  the  associated  activity 
of  the  sweat  glands  so  favors  heat  escape,  that  the  injurious  effect  of 
excessive  body  heat  is  prevented.  Again,  the  viscera  concerned  in 
digestion  (notably  the  liver)  generate  much  heat;  by  the  blood  it  is 
carried  to  the  cooler  extremities. 

A  high  temperature  of  the  surrounding  atmosphere  so  affects 
the  nerve  centers,  that  the  respiratory  function  is  stimulated 
and  evaporation  from  the  lungs  increased,  at  the  same  time 
activity  of  the  skin  is  very  marked  and  evaporation  of  perspiration 
follows. 

These  natural  processes  of  mutual  accommodation  result  in 
preserving  a  necessary  uniform  temperature  of  the  body,  which 
makes  it  independent,  within  reasonable  limits,  of  external  surround- 
ings. The  normal  temperature,  98.4°  F.,  is  maintained  so  long  as 
heat  production  and  heat  escape  are  properly  adjusted  to  each  other. 
Elevation  of  temperature  is  caused  when  production  is  too  rapid  or 
dissipation  is  too  slow.  Very  high  temperature  indicates  excessive 
metabolism  and  impaired  dissipation.  (Another  result  of  excessive 
metabolism  is  seen  in  the  "wasting  of  the  body  in  fevers,  as  typhoid 
fever.) 

Subnormal  temperature  indicates  diminished  Lissue  change  or 
metabolism,  suggesting  impairment  of  vitality.  (A  temperature  of 
77°  F.  is  followed  by  death,  as  cell  activity  cannot  go  on  in  a 
temperature  so  low.) 

Range  of  normal  temperature. — The  normal  adult  tempera- 
ture is  98.4°  F.  in  the  axilla,  in  the  mouth  slightly  higher.  It  is  a 
degree  higher  in  the  rectum. 

During  early  life  when  metabolism  is  active  it  is  slightly  higher 
than  in  later  years.  In  old  age  it  is  often  a  degree  higher  than  in 
middle  life. 

A  difference  of  a  degree  is  noted,  in  health,  between  the 
temperature  of  early  morning  and  evening,  for  example,  at  5  A.  m. 
and  5  p.  M. 


228  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

Average  range  of  body  temperature  for  different  ages: 

In  infancy 99 — 99.5 

At  puberty 99 

In  adult  life: 

Axillary 98.4 

Oral 98.8 

Rectal 99.2 

Practical  Conclusions  and  Clinical  Notes. 

The  temperature  of  a  patient  should  be  taken  before  a  meal, 
or  after  digestion,  not  during  it. 

In  cold  weather  hot  foods  containing  fats  are  appropriate  for  the 
generation  of  heat;  in  hot  weather  starchy  foods  and  cool  drinks  are 
in  order. 

Alcohol  causes  a  temporary  sense  of  warmth  by  quickening  the 
circulation,  but  this  is  followed  by  dilation  of  the  surface  capillaries 
and  a  consequent  radiation  of  heat.  The  use  of  alcohol  before 
exposure  to  a  low  temperature  should  be  avoided,  unless  some  very 
reliable  measure  is  taken  for  preventing  surface  radiation. 

Muscle  exercise  is  accompanied  by  dilation  of  surface  vessels 
and  escape  of  heat;  this  continues  for  some  tirne  after  the  exercise 
has  ceased,  therefore,  care  should  be  taken  to  guard  against  too 
great  loss  of  heat  and  a  consequent  "cold"  due  to  chilling  of  the 
surface,  especially  when  exposed  to  a  draft  of  air. 

The  fact  that  the  body  loses  heat  rapidly  by  conduction,  should 
warn  the  nurse  against  putting  cold  garments  on  a  delicate  patient, 
and  especially  against  placing  a  patient  in  a  cold  bed.  Remember 
that  the  body  of  the  patient  must  furnish  the  heat  to  warm  the  bed 
and  this  makes  an  unnecessary  demand  upon  vitality  already 
impaired  by  illness. 


CHAPTER  XVI. 

THE  NERVE  SYSTEM. 

NERVE  TISSUES  AND  THE  SPINAL  CORD. 

The  foundation  cells  of  which  nerve  tissues  are  composed  are 
microscopic  in  size  and  called  neurons.  A  neuron  consists  of  a  nucle- 
ated cell  body,  an  axan,  and  terminal  divisions. 

The  cell  body  has  short  branches  called  dendrites,  one  of  which 
(sometimes  two)  grows  longer  to  form  the  axon  or  axis  cylinder  which 
becomes  a  nerve  fiber. 

Note. — The  term  nerve  cell  is  often  used  to  signify  the  cell  body  of  a  neuron. 


Dendrites 


Xcrve  cell 


Medullated 
liber 


Xerve  cell 


Fig.  i6i.  I.ig_  ^,,2. 

Figs.   i6r,   162.— Nerve  Cells  (Brubaker). 

When  the  axon  is  invested  with  a  sheath,  the  medulla,  it  is  a 
medidlated  nerve  fiber,  and  such  are  found  in  voluntary  muscles  and 
all  sensitive  parts  of  the  body.     Axons  without  sheaths  are  known 

229 


230  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

as  non-medulated  nerve  fibers,  and  such  are  found  in   involuntary 
muscles  and  in  the  walls  of  internal  organs. 

Structures  composing  a  medullated  nerve  fiber: 

1.  The  axon  or  axis-cylinder. 

2.  Medulla  or  myelin  (white  substance  of  Schwann). 

3.  Neurilemma,  a  transparent  membrane  inclosing  the  myelin  (sometimes 
absent) . 

Structures  composing  a  non-medullated  nerve  fiber: 

1.  The  axon  or  axis -cylinder. 

2.  Neurilemma  (sometimes  absent). 

Medullated  nerves  are  found  in  voluntary  muscles,  skin,  mucous  and  serous 
membranes,  joints  and  special  sense  organs. 

Non-medullated  nerves  are  found  in  glands,  vessels,  hollow  viscera,  and 
muscle  fibers  at  roots  of  hairs. 

The  axons  or  nerve  fibers  terminate  in  fine  branches,  which 
connect  them  either  with  various  organs  or  with  the  dendrites  of 
other  cell  bodies,  as  the  case  may  be. 

For  want  of  more  accurate  language,  we  say  that  impulses  are 
transmitted  through  fibers  either  to  or  from  cell  bodies.  If  to  the 
body,  the  fiber  and  cell  constitute  an  afferent  neuron  (afferent,  bearing 
toward);  \ifrom  the  cell  body  the  neuron  is  efferent  (efferent,  bearing 
away). 

Important  to  remember. — The  cell  body  is  necessary  to  the  life 
of  the  fiber. 

THE  TWO  DIVISIONS  OF  THE  NERVE  SYSTEM— 
CEREBRO-SPINAL,  SYMPATHETIC.^ 

The  Cerebro-spinal  Division  of  the  Nerv:e  System. 

The  brain  and  spinal  cord  with  their  nerves  constitute  the 
cerebro-spinal  system,  and  since  the  brain  and  cord  contain  the 
largest  and  most  important  centers,  this  is  often  called  the  central 
nerve  system  (Fig.  163). 

Nerve  tissues  in  the  cerebro-spinal  system  appear  to  the  eye 
as  of  two  kinds,  gray  and  white.  The  gray  tissue,  commonly  called 
"gray  matter,"  is  composed  of  cell  bodies  and  their  branches.  The 
so-called  "white  matter"  is  composed  of  medullated  fibers  belonging 
to  the  cells. 

^  For  description  of  the  Symphathetic  Division  see  page  262. 
^  For  description  of  the  Brain  and  Cranial  Nerves  see  page  249. 


NERVES  AND  NERVE  CENTERS. 


231 


A  nerve  (of  the  cerebro-spinal  system)  consists  of  many  fibers 
bound  together;  it  resembles  in  appearance  a  white  cord  and  may  be 
so  small  as  to  be  distinguished  with  difficulty,  or  as  large  as  a  child's 
finger — like  the  great  sciatic  nerve. 


A  nerve  is  constructed  after  the  same  plan  as  that  of  a  muscle.  A  connective 
tissue  sheath  {epi-ncnriiini)  sends  partitions  {peri-neurium)  between  bundles  of 
fibers,  and  a  delicate  membrane  {endo-neurium)  sur- 
rounds each  fiber. 

Nerves  divide  into  branches  which  may  interlace 
with  others  or  join  them  in  a  common  sheath,  but 
no  fiber  ever  unites  with  another.  Each  one  con- 
tinues throughout  the  length  of  the  nerve  of  which  it 
forms  a  part. 

Nerve  centers  are  the  gray  cell  bodies  to 
which  nerves  belong,  and  which  are  necessary 
to  the  life  of  the  fibers. 

This  term  is  commonly  used  to  signify 
a  collection  of  cells  whose  fibers  form  nerves 
having  a  special  function,  or  which  preside 
over  a  group  of  movements.  (A  definite 
collection  of  gray  cells  is  also  called  a 
ganglion.)  Motor  nerves  transmit  motor  im- 
pulses from  centers  to  muscles,  while  sensory 
nerves  transmit  impressions  from  the  various 
parts  of  the  body  to  the  centers  which  receive 
them.  (We  commonly  speak  of  motor  nerves 
as  running  down,  and  sensory  nerves  as  run- 
ning up,  referring  them  to  the  spinal  cord 
or  brain.) 

The  Spinal  Cord, 


Fig.  163. — The  Brain 
AND  Spinal  Cord 
(Quain,  after  Bourgery). 


The  spinal  cord  lies  within  the  spinal 
canal  in  the  spinal  column,  being  continuous 
with  the  brain.     It  is  a  round  white  structure 

about  seventeen  inches  long,  extending  from  the  atlas  to  the  second 
lumbar  vertebra,  where  it  ends  in  a  slender  terminal  filament  which 
continues  to  the  end  of  the  canal.  The  thickness  is  about  half  an 
inch,  being  greater  in  the  lower  cervical  and  lower  dorsal  regions, 
making   the    cervical   and  lumbar  enlargements  where   nerves  are 


232 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


given  off  for  the  extremities.     It  presents  a  median  fissure  in  front 

and  another  at  the  back,   marking  off.  its  right  and  left  halves. 

Other  fissures  divide  each  half  into  anterior,  lateral,  and  posterior 

columns  or  tracts. 

A  transverse  section  will  show  that  the  interior  of  the  cord  is 

grayish  in  color  instead  of  white,  and  this  portion  is  largely  made  up 

of  the  gray  cell-bodies  and  their  branches, 
arranged  in  masses  which  are  continuous 
throughout  the  length  of  the  cord. 

The  section  will  also  show  that  the 
area  occupied  by  the  gray  portion,  roughly 
resembles  two  crescents  (one  in  either 
side),  connected  together  across  the  mid- 
dle. The  extremities  of  the  crescents  are 
called  the  anterior  and  posterior  horns. 

A  canal  runs  through  the  center  of 
the  gray  portion  called  the  central  canal, 
which  may  be  traced  throughout  the  length 
of  the  cord,  but  is  easily  seen  only  in  the 
upper  part. 

The  white  portion  consists  of  the  bun- 
dles or  tracts  of  the  cord.  There  is  a 
general  division  into  three  in  each  half — 
the  anterior,  lateral,  and  posterior  tracts. 
The  fibers  in  the  anterior  and  a  portion 
of  the  lateral  tracts  are  connected  with  the 
cells  of  the  anterior  horn.  They  conduct 
motor  impulses.  The  fibers  in  the  poste- 
rior and  a  portion  of  the  lateral  tracts 
are  connected  with  the  posterior  horn,  and 
conduct  sensory  impressions. 


Fig.  164. — Three  Sections 
OF  Spinal  Cord. 
A,  Cervical  region;  B, 
thoracic  region;  C,  lumbar 
region;  p,  posterior  horn;  a 
anterior  horn  (Holden) . 


Membranes  of  the  Spinal  Cord. 


The  pia  mater. — A  delicate  membrane  which  bears  the  blood- 
vessels and  is  very  closely  applied  to  the  surface  of  the  cord  (the 
vascular  membrane  of  the  cord). 

The  arachnoid  (web-like). — Outside  of  the  pia  mater.-  A  serous 
membrane  containino;  fluid  to  make  a  water-cushion  for  the  cord. 


MENINGES    OF    THE    CORD. 


233 


The  dura  mater.— A  strong  white  fibrous  membrane,  tubular  in 
shape,  in  which  the  cord  is  loosely  suspended.  It  is  attached  above 
to  the  margin  of  the  foramen  magnum. 

The  space  between  the  dura  and  the  arachnoid  is  the  subdural 
space;  that  between  the  arachnoid  and  pia  is  the  subarachnoid  space; 
they  contain  cerebrospinal  fluid.  The 
subarachnoid  space  is  largest,  in  the 
lower  portion.  (The  fluid  in  this 
space  mixes  with  that  of  the  central 
canal  through  a  small  opening  in  the 
pia,  at  the  base  of  the  brain.) 

The  membranes  are  also  called  the 
meninges,  and  their  blood-vessels  are 
the  meningeal  vessels.  Spinal  menin- 
gitis is  inflammation  of  the  meninges 
of  the  cord. 

Surgical  note. — The  operation  of  lumbar 
puncture  is  for  the  purpose  of  opening  the 
dura  and  arachnoid  and  drawing  off  a  cer- 
tain quantity  of  cerebro-spinal  fluid. 

Spinal  Nerves. 

A  spinal  nerve  is  a  collection  of 
motor  and  sensory  fibers  connected 
with  the  spinal  cord  by  two  roots — an 
anterior  root  running  from  the  motor 
cells  and  tracts  and  a  posterior  root 
running  to  the  sensory  tracts  and  cells. 

The  two  roots  become  imbedded  in  one  sheath  at  the  interverte- 
bral  foramen  which  transmits  the  nerve  from  the  spinal  canal. 


Fig.  165. — Membranes  of 
Spinal  Cord. 

I,  Dura  mater;  2,  arachnoid; 
3,  post,  root  of  nerve;  4,  ant.  root 
of  nerve,  divided;  5,  pia  mater;  6, 
linea  splendens  (Morris,  after 
Ellis). 


Note. — The  "ganglion  of  the  root"  is  a  small  ganglion  on  the  posterior 
root  where  the  true  root  fibers  arise. 

The  ganglion  contains  the  cell-bodies  of  fibers  in  the' posterior  roots:  they  are 
necessary  to  the  life  of  these  roots.  Two  axons  arise  from  each  ganglion  cell ; 
one  becomes  part  of  a  spinal  nerve  and  ends  in  a  sensitive  part  of  the  body 
(skin,  mucous  membrane,  muscle  tissue  and  lining  of  joints) ;  the  other  forms  a 
fiber  of  the  posterior  root  of  the  same  spinal  nerve,  and  enters  the  cord  to  become 
associated  with  cells  of  both  posterior  and  anterior  horns.  (The  fibers  of  the 
anterior  roots  arise  in  the  cells  of  the  anterior  horns.) 


234  ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 

Clinical  note. — Since  the  spinal  nerves  contain  both  motor  and  sensory 
fibers,  they  are  called  mixed  nerves;  and  since  the  antero-lateral  divisions  of  the 
cord  are  motor  tracts,  and  the  postero-lateral  divisions  are  sensory  tracts,  we 
can  understand  how  injury  in  one  region  will  cause  paralysis  of  motion,  and 
injury  in  the  other  will  cause  paralysis  of  sensation;  while  injury  of  a  mixed  nerve 
will  cause  loss  of  both  motion  and  sensation  in  the  parts  to  which  the  nerrc 
belongs. 


CHAPTER  XVII. 

THE  SPINAL  NERVES. 

There  are  thirty-one  pairs  of  spinal 
nerves.  They  leave  the  spinal  canal  at 
the  intervertebral  foramina  in  the  differ- 
ent regions  and  are  named  accordingly. 

Cervical 8 

Thoracic 12 

Lumbar 5 

Sacral 5 

Coccygeal i 

The  first  cervical,  emerging  above  the  atlas, 
is  called  the  suboccipital. 

The  Cauda  equina. — The  spinal  cord,  being 
17  inches  long,  reaches  only  to  the  second  lumbar 
vertebra,  therefore  the  nerves  emerging  through 
the  foramina  below  this  level  must  have  lain  in 
the  canal  for  some  distance  before  leaving  it, 
especially  those  vi^hich  appear  in  the  lowest  or 
pelvic  region.  If  the  canal  be  opened  at  the 
back  and  the  cord  lifted  out,  these  long  nerves 
are  seen  hanging  from  it  in  a  crowd,  suggesting 
the  appearance  of  a  horse's  tail,  the  "cauda 
equina,"  which  therefore  is  composed  of  the 
lumbar,  sacral,  and  coccygeal  nerves  while  they 
are  still  in  the  neural  canal.  The  terminal 
filament  extends  dowTiward  in  their  midst. 

All  spinal  nerves  divide  at  once  into 
posterior  and  anterior  divisions,  both 
divisions  containing  motor  and  sensory 
fibers  (Fig.  168). 

The  posterior  divisions  send  nerves  to 
posterior  regions  of  neck  and  trunk;  the 
anterior  divisions  (communicate  with  the 
sympathetic  system,  and  then)  send 
nerves  to  anterior  and  lateral  regions  of 
the   neck  and  trunk,  and  to  the  upper 

235 


8  Cervical 


12  Thoracic 


\ 


5  Lumbar 


5  Sacral 

Fig.  166. — Diagram  of 
Spinal  Nerves. 


236 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


and  lower  extremities/  In  all  regions  except  the  thoracic,  the  an- 
terior divisions  interlace  with  each  other  to  form  plexuses  before 
giving  off  nerves. 

The  most  important  plexuses  are: 

The  cervical  plexus  (formed  by  the  upper  four 
cervical  nerves). 

The  brachial  plexus  (formed  by  the  lower  four 
cervical  and  jirst  thoracic  nerves). 

The  lumbar  plexus  (formed  by  the  upper  three 
and  part  of  the  fourth  lumbar  nerves). 

The  sacral  plexus  (formed  by  the  lower  lumbar, 
and  upper  three  and  most  of  fourth  sacral  nerves) . 

The  larger  nerves  only  are  described  in  the 
text.     Resumes  are  added  for  reference. 

For  nerves  supplying  the  joints  see  page  69. 


CERVICAL  NERVES. 

Posterior  divisions. — These  send  branches 
to  the  back  of  the  head  as  well  as  muscles 
and  skin  of  the  neck.  Largest  posterior 
branch. — The  great  occipital  (from  second 
cer\dcal),  to  supply  the  scalp. 

Anterior  divisions. — The  upper  four 
form  the  cervical  plexus.  The  lower  four 
enter  the  brachial  plexus. 


Fig.  167. — Cauda  Equina 
(Morris) . 


Fig.  168. — Showing  Division  of  Nerve. 
I,  Dura  mater;  2,  arachnoid;  3,  ganglion 
of  post,  root;  4,  ant.  root;  5,  space  contain- 
ing spinal  fluid;  6,  post,  division  of  nerve 
(Holden). 


The  cervical  plexus. — Most  of  the  branches  of  this  plexus 
supply  muscles  of  the  neck  (front  and  side).     One  exception  is  the 

*  The  communicating  branches  to  sympathetic  ganglia  are  of  great  importance, 
serving  to  connect  the  cerebro-spinal  and  sympathetic  division  into  one  great  nerve 
svstem. 


THE    PHRENIC    NERVE. 


237 


great  auricular  {auricularis  magnus)  which  supplies  the  external  ear. 
Another  is  the — - 

Most  important  nerve  of  this  plexus,  the  phrenic. — It  passes 
downward  through  the  thorax  (between  the  lung  and  heart)  to 
supply  the  diaphragm  (Fig.  169).  Its  importance  is  due  to  the  fact 
that    the   diaphragm   is  one   of   the  principal  breathing  muscles, 


Fig.  169. — The  Phrenic  Nerves,  Right  and  Left,  run  downward  on  either 
Side  of  the  Great  Vessels  and  the  Heart  (After  Morris). 


and  the  nerve  has  for  that  reason  been  called  the  "internal  respiratory 
nerve  of  Bell."  (Sir  Charles  Bell  was  a  famous  anatomist  in  former 
times.) 

The  brachial  plexus. — This  plexus  is  so  named  because  most 
of  its  branches  supply  muscles  of  the  upper  extremity  (including 
the  shoulder)* and  those  connected  with  it. 

First  important  branch,  given  off  in  the  neck— the  long  thoracic. 
It  passes  downward  along  the  side  of  the  thorax  to  supply  the  anterior 


238  ANATOMY   AND    PHYSIOLOGY    FOR   NURSES. 

serratus  muscle  (p.  95).  This  muscle  is  used  in  forced  respiration 
and  the  nerve  has  been  called  therefore  the  ^^  external  respiratory 
nerved 

The  greater  part  of  the  branchial  plexus  is  situated  in  the  axilla; 
most  of  its  branches  are  given  off  there 

T)         1.  c   A  ^  7       ^        [  supraspinatus 

Branches:  Suprascapular,  to      {  .    '       . 

[  infraspinatus 

Three  large  cords:         Lateral,  medial,  posterior. 

Branches  of  the  cords: 

From  lateral  cord:  Thoracic,  to  pectoral  muscles. 

Musculo-cutaneous,  to  biceps  and  brachialis  (and 

their  integument). 

Upper  root  of  median  nerve. 

From  medial  cord :         Lower  root  of  median  nerve. 

Thoracic,  to  pectoral  muscles. 

Cutaneous,  to  integument  of  forearm. 

Ulnar,  to  ulnar  muscles. 

[  subscapularis,    teres    major, 

From  posterior  cord:      Subscapular  to       ]  latissimus     dorsi    (the    long 

[  subscapular). 

Axillary,  to  deltoid  and  teres  minor. 

Radial,  to  posterior  of  forearm  and  hand. 

The  three  large  nerves  derived  from  the  brachial  plexus  are: 

The  ulnar  from  the  medial  cord. 

The  median  from  the  medial  and  lateral  cords. 

The  radial  from  the  posterior  cord. 

The  ulnar  nerve  runs  downward  in  the  medial  side  of  the  arm, 
passes  behind  the  medial  epicondyle  into  the  forearm,  and  ends  in 
the  palm  (Fig  170). 

In  the  forearm  it  supplies:    Flexor  carpi  ulnaris. 

Flexor  digitorum  (profundus). 
In  the  hand  it  supplies:         Interossei. 

Little  finger  muscles. 

Thumb  muscles  (one  and  a  half). 

The  median  nerve  runs  downward  in  the  arm,  close  under  the 
border  of  the  biceps  muscle.  It  then  passes  in  front  of  the  elbow 
joint  into  the  forearm,  and  continues  between  the  layers  of  flexor 
muscles  to  the  palm. 


BRACHLA.L    PLEXUS   AND    BRANCHES. 


239 


Axillary  artery 


Median  nerve 
Brachial  artery 


Suprascapular  nerve  and  artery 


Lateral  ^^ 

cord 


Pectoral 
muscle 


Ulnar  nerve  and 

artery 
Radial  nerve  and 

artery 


Branches  to  hand 


^      ^ 


Fig.  170. — Brachial  Plexus  and 
Anterior  Nerves. 


Post,  interosse 
ous  nerve 


Fig.  171. — The  Radial  Nerve. 


24©  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

In  the  forearm  it  supplies:  Flexor  carpi  radialis. 

Flexor  digitorum  (sublimis). 

Flexor  digitorum  profundus  (partially). 

Supinator. 

In  the  hand  it  supplies:  Thumb  muscles  (except  one  and  a  half). 

The  radial  nerve  passes  to  the  back  of  the  arm,  winding  across 
the  humerus  in  the  radial  groove,  under  the  triceps  muscle  (Fig. 
171). 

Just  above  the  elbow  it  divides  into  two  branches,  the  deep  and 
superficial  branches  of  the  radial  nerve. 

The  superficial  branch  is  a  cutaneous  nerve.  It  runs  downward 
in  the  radial  side  of  the  forearm  to  supply  integument  of  the  hand 
and  fingers  posteriorly. 

The  deep  branch  passes  to  the  back  of  the  forearm,  lying  under 
cover  of  extensor  muscles,  all  of  which  it  supplies. 

Branches  of  the  radial  nerve: 

In  the  arm: To  the  triceps. 

To  brachio-radialis. 
To  brachialis  (partially). 

Branches  of  the  deep  branch  of  the  radial  nerve: 

In  the  forearm: To   the   extensor  carpi  radialis    (long   and 

short) . 
To  the  extensor  digitorum  (comunis). 
To  the  extensor  of  index  finger. 
To  the  extensor  of  little  finger. 
To  the  extensors  of  the  thumb. 

Resume. — The  general  distribution  of  the  muscle  nerves  arising 
from  the  brachial  plexus,  is  to  deep  muscles  of  the  neck  and  the 
external  respiratory  muscle  (anterior  serratus);  to  shoulder  and 
axillary  muscles;  arm,  forearm  and  hand. 

The  three  long  muscular  nerves  derived  from  the  brachial  plexus 
are  the  ulnar  nerve  from  the  medial  cord,  running  down  behind 
the  medial  epicondyle  into  the  forearm  and  hand  (supplying  ulnar 
muscles,  little  finger  muscles  and  the  interossei,  and  a  part  of  the 
thumb  group) ;  the  median  nerve  from  the  medial  and  lateral  cords, 
running  down  along  the  medial  border  of  the  biceps  muscle  into  the 
forearm,  to  end  in  the  palm  (supplying  the  biceps  and  brachial 
muscle,  all  of  the  flexors  of  the  forearm  except  on  the  ulnar  side, 


ULNAR,    MEDIAN,    AND    RADL\L    NERVES. 


241 


and  most  of  the  thumb  muscles);  the  radial  nerve  from  the  pos- 
terior cord,  running  in  its  groove  to  the  front  of  the  lateral  epicondyle, 
and  dividing  into  the  deep  and  superficial  branches  of  the  radial 
nerve.  By  the  radial  and  its  deep  branch  all  of  the  posterior  muscles 
of  the  arm  and  forearm  are  supplied, 

Nerves  of  the  skin  of  the  hand. — Front  of  the  thumb,  index, 
middle,  and  one-half  of  the  ring  finger,  the  median  nerve  Back  of 
thumb,  index,  middle,  and  one-half  of  ring  finger,  the  superficial 
branch  of  the  radial  nerve.  Both  front  and  hack  of  little  finger  and 
one-half  of  ring  finger,  the  idnar  nerve. 


Fig.  172. — Dorsal  SunrACE  of  Left 
Hand  (Morris). 


Fig. 


173- 


-An  Intercostal  Nerve 
(Holden). 


Points  of  interest. — The  ulnar  nerve  in  the  arm  is  with  the  inferior  pro- 
funda artery  and  passes  behind  the  medial  epicondyle;  it  may  be  easily  felt  in 
the  groove  behind  the  epicondyle,  where  pressure  causes  a  sensation  of  pain  and 
tingling  as  far  as  the  little  finger.  In  the  forearm  it  is  on  the  ulnar  side  of  the 
ulnar  artery  and  they  pass  in  front  of  the  wrist. 

The  median  nerve,  in  the  arm,  is  with  the  biceps  muscle  and  brachial  artery, 
and  they  pass  in  front  of  the  elbow;  in  the  forearm,  it  lies  between  the  deep  and 
superficial  muscles  and  passes  with  their  tendons  in  front  of  the  wrist. 

The  radial  nerve  lies  in  the  groove  for  the  radial  nerve  between  two  heads  of 
the  triceps  muscle,  with  the  superior  profunda  artery,  and  comes  to  the  front  of 
the  elbow. 

The  superficial  branch  of  the  radial  nerve  in  the  front  of  the  forearm  is  on  the 
radial  side  of  the  radial  artery;  it  winds  around  behind  the  wrist-joint. 

The  deep  branch  of  the  raial  nerve  is  in  the  back  of  the  forearm  with  the 
dorsal  interosseous  artery;  they  do  not  extend  below  the  wrist. 

Note. — For  the  distribution  of  nerves  to  the  principal  joints,  see 
page  69. 
16 


242 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


THORACIC  NERVES  (FIG.  173). 

There  are  twelve  pairs  of  thoracic  nerves: 

Posterior  divisions. — These  send  branches  to  muscles  and  skin 
of  the  back. 

Anterior  divisions. — These  form 
the  intercostal  nerves;  the  first  assists 
in  the  formation  of  the  brachial  plexus. 
All  run  in  the  grooves  under  the 
borders  of  the  ribs,  supplying  inter- 
costal muscles  and  the  upper  portion 
of  the  abdominal  muscles,  also  the 
skin  over  the  muscles.  They  accom- 
pany intercostal  arteries. 

LUMBAR  NERVES 

There  are  five  pairs  of  Lumbar 
Nerves. 

Posterior  divisions. — These  send 
branches  to  muscles  of  the  back;  and 
skin  of  the  back,  hip,  and  sacral 
region. 

Anterior  divisions. — The  upper 
three  and  a  portion  of  the  fourth  form 
the  lumbar  plexus.  The  remainder  of 
the  fourth  and  the  whole  of  the  fifth 
form  the  lumbosacral  cord  (Fig.  174). 

The  lumbar  plexus. — This  plexus 
lies  within  the  abdomen,  in  the  sub- 
stance of  the  psoas  muscle.  Its 
branches  supply  abdominal  walls, 
and  front  and  sides  of  the  thigh  (also 
integument  of  both  regions).  They 
are  all  given  off  in  the  abdomen.. 


Fig.  174. — The  Femoral  Nerve. 
I,  Femoral  nerve;  2,  3,  small 
nerves  from  lumbar  plexus;  4,  5, 
6,  7,  8,  9,  10,  II,  II,  branches  of 
femoral  nerve;  12,  12,  13,  14,  long" 
saphenous  nerve  and  its  branches; 
15,  obturator  nerve;  16,  17,  18,  19, 
branches  of  obturator  nerve;  20, 
21,  lumbo-sacral  cord;  23,  ex- 
ternal cutaneous  nerve  (Gould's 
Dictionary). 


Branches:  the  principal  are: 

Ilio -hyp agastric,  cutaneous  to  hypogastrium,  and  over  the  ilium  (dorsum). 
Inguinal,  to  internal  oblique  and  transversus  muscles. 
Genito-femoral,  to  round  ligament  of  uterus,  cremaster  muscles  of  sper- 
matic cord. 


THE    GREAT    SCIATIC    NERVE.  243 

Obturator,  to  the  external  obturator  and  the  four  adductors. 
Femoral,  to  the  quadriceps  muscle  (rectus  and  three  vasti). 

The  femoral  nerve  {anterior  crural)  is  the  largest  branch  of  the 
lumbar  plexus.  It  passes  from  the  abdomen,  under  the  inguinal 
ligament,*  into  the  thigh  (on  the  lateral  side  of  the  femoral  artery), 
and  breaks  up  at  once  into  branches — cutaneous  and  muscular,  for 
the  four  large  divisions  of  the  quadriceps  extensor  muscle  and  the 
integument  which  covers  them. 

The  long  saphenous  branch  of  the  femoral  nerve  is  the  longest 
nerve  in  the  body,  running  nearly  the  whole  length  of  the  extremity; 
it  supplies  integument  only,  on  the  medial  side  of  the  leg  and  foot. 
•       The  lumbo-sacral  cord  passes  into  the  pelvis  to  unite  with  sacral 
nerves  and  to  form  the  sacral  plexus. 


SACRAL  NERVES. 

Posterior  divisions. — These  send  branches  to  muscles  and  skin 
of  the  back  of  the  pelvis. 

Anterior  divisions. — The  upper  three,  and  greater  part  of  the 
fourth,  join  the  sacral  plexus. 

The  sacral  plexus. — The  branches  of  this  plexus  supply  the 
muscles  within  and  around  the  pelvis,  the  posterior  part  of  the  thigh, 
and  the  entire  leg  and  sole  of  the  foot. 

Branches:  (All  leave  the  pelvis  through  the  great  sciatic  foramen.) 

Gluteal,  two  {superior  and  inferior)  to  glutei  muscles. 

Pudic,  to  the  levator  ani,  rectum  (sphincter  ani),  perineum,  and  external 
genital  organs. 

Small  sciatic,  to  posterior  thigh  and  external  genital  organs.  This  is  a  cuta- 
neous nerve. 

Great  sciatic,  to  posterior  thigh,  and  entire  leg  and  foot  (except  medial  bor- 
der) muscles  and  skin. 

The  great  sciatic  nerve  is  the  largest  nerve  in  the  body.  It 
leaves  the  pelvis  by  way  of  the  great  sciatic  notch  and  runs  downward 
between  posterior  thigh  muscles  to  the  popliteal  space,  where  it 
divides  into  tibial  and  common  peroneal  nerves  (Fig.   175). 

The  only  portion  of  the  great  sciatic  nerve  which  is  not  covered 
by  muscles,  lies  in  the  deep  groove  between  the  great  trochanter  of 
the  femur  and  the  tuberosity  of  the  ischium. 


244 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES, 


Branches: 


To  the  Biceps, 

Semitendinosus. 
Semimembranosus. 


\Gt,iiSeu,s\^e, 


■  Gluteal    n. 


7, 


—    Sciatic  n. 


f-jf -'   Popliteal  artery 

-  Tibial  n. 


Peroneal  n. 


Ant.  tib.  artery 


Tibial  n. 

Post.  tib.  artery 


Fig.  175. — The  Sciatic  Nerve. 


The  division  of  the  great  sciatic 
nerve  occurs  in  the  upptr  part  of 
the  popHteal  space.  The  tibial 
nerve  {internal  popliteal)  runs  down 
through  the  popliteal  space  (with 
the  popliteal  artery  and  vein)  to  the 
leg.  It  then  descends  under  cover 
of  the  calf  muscles  to  the  ankle;  be- 
low the  medial  malleolus  it  divide^ 
into  medial  and  lateral  plantar 
nerves. 
Branches: 

In  the  leg. — To  the  Tibialis  posticus. 
Flexor  digitorum  (longus). 
Flexor  hallucis. 
In   the  foot. — By  medial  plantar,  to 
great  toe  muscles  and  interossei. 
By  lateral  plantar,  to  muscles  of 
little  toe. 
The  tendons  of  the  first  three  (tibialis 
and  two  long  flexors  of  toes)  pass  behind 
the  lateral  malleolus.   They  extend  the  foot. 

The  common  peroneal  nerve 
{external  popliteal)  winds  round  the 
neck  of  the  fibula  to  the  front  of  the 
leg,  and  divides  into  the  deep  pero- 
neal and  superficial  peroneal  nerves. 
The  deep  peroneal  (formerly  an- 
terior tibial)  descends  to  the  ankle, 
and  ends  on  the  dorsum  of  the  foot 
between  the  jBrst  and  second  toes. 
Branches: 

In  the  leg. — To  the  Tibialis  anticus. 
Extensor  hallucis. 
Extensor  digitorum  (longus). 
Peroneus  tertius. 
In    the    foot. — Extensor    digitorum 
(brevis). 


PHYSIOLOGY    OF    SPINAL    CORD. 


245 


The  tendons  of  the  muscles  in  the  leg — (tibialis,  two  long  extensors  of  toes, 
and  one  peroneus)  pass  in  front  of  the  ankle-joint.     Thty  flex  the  foot. 

The  superficial  peroneal  (musculo-cutaneous)  runs  downward  in 
the  substance  of  the  peroneal  muscles  to  the  foot. 

Branches: 

Muscular. — To  the  Peroneus  longus,  peroneus  brevis. 
Cutaneous. — To  dorsum  of  foot. 

Their  tendons  pass  behind  the  lateral  malleolus.     They  extend  the  foot. 

Points  of  interest. — The  superior  gluteal  nerve,  with  the  superior  gluteal 
artery;  the  sciatic  nerve,  with  the  sciatic  artery;  and  the  pudic  nerve,  with  the 
pudic  artery,  all  pass  out  from  the  pelvis  through  the  great  sciatic  foramen;  the 
pudic  nerve  and  artery  return  through  the  small  sciatic  foramen. 

The  obturator  nerve  and  the  obturator  artery  pass  through  the  obturator 
foramen. 

The  femoral  nerve  is  on  the  lateral  side  of  the  femoral  artery,  under  the 
inguinal  ligament. 

THE  COCCYGEAL  PLEXUS. 

The  remaining  sacral  nerves  and  the  coccygeal  nerve  communi- 
cate in  a  small  plexus,  which  is  important  in  that  it  sends  branches 
to  the  viscera  of  the  pelvis. 

Summary. 

The  spinal  nerves  are  distributed  to  all  skeletal  muscles  and 
integument  except  those  of  the  front  of  the  head,  face,  and  chin. 
Through  sympathetic  connections  they  also  supply  secreting  cells 
of  glands  and  walls  of  viscera. 

FUNCTIONS  OR  PHYSIOLOGY  OF  THE  SPINAL  CORD 
AND  SPINAL  NERVES. 

The  spinal  cord  is  so  intimately  connected  with  the  brain  by 
conducting  fibers  in  the  tracts,  that  it  is  impossible  to  explain  all 
of  its  functions  without  referring  to  the  brain,  but  certain  ones  may 
be  exercised  independently,  and  a  few  of  these  will  be  considered 
briefly  in  this  connection. 

The  spinal  cord  a  center  for  reflex  action.  This  is  one  of  the 
most  important  of  its  functions  and  the  simplest  form  of  nerve 
and  muscle  action.  (Acts  which  may  be  performed  without 
thinking  of  them  are  reflex.) 


246 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


We  have  already  seen  that  the  cord  comprises  an  interior 
portion  of  gray  nerve  tissue  surrounded  by  white;  cell  bodies  and 
their  branches  forming  the  central  gray  portions  and  white  fibers 
forming  the  columns  or  tracts. 

In  each  lateral  half  of  the  cord  the  cell  tissue  is  grouped  in 
crescents.  Fibers  in  the  posterior  tracts  transmit  sensory  impulses 
from  various  parts  of  the  body  to  cells  in  the  posterior  horns  of  the 
crescents.  Fibers  in  the  anterior  tracts  transmit  motor  impulses 
■from  cells  in  the  anterior  horns  to  various  parts  of  the  body  (their 
axons  arise  in  cells  of  the  anterior  horns)  (Fig.   176). 


.spc. 


Fig.  176.  Diagram  Showing  the  Structures  Involved  in  the  Production 
OF  Reflex  Actions  (G.  Bachman).  r.s.  Receptive  surface;  af.n.  afferent  nerve; 
e.c.  emissive  or  motor  cells  in  the  anterior  horn  of  the  gray  matter  of  the  spinal  cord, 
sp.c;  ef.n.  efferent  nerves  distributed  to  responsive  organs,  e.g.,  directly  to  skeletal  mus- 
cles, sk.vt.,  and  indirectly  through  the  intermediation  of  sympathetic  ganglia,  sym.  g., 
to  blood  vessels,  b.v.,  and  to  glands,  g.  The  nerves  distributed  to  viscera  are  not 
represented. 


Here  we  have  the  apparatus  for  reflex  muscle   action. — A 

sensory  or  afferent  nerve  receives  an  impression,  and  transmits  a 
series  of  impulses  to  the  spinal  cord.  These  are  received  by  a  cell 
which  in  its  turn  is  stimulated,  and  liberates  energy  to  be  con- 
ducted by  a  motor  or  efferent  nerve  to  a  muscle,  and  the  muscle 
contracts.     This  act  is  comparatively  simple. 

Most  muscle  activities,  however,  are  complex,  requiring  the  com- 
bined action  of  several  organs;  in  these  cases  many  motor  cells  and 
nerves  must  be  stimulated,  and  this  is  accomplished  by  means  of 


REFLEX   ACTION.  247 

additional  neurons  within  the  cord,  whose  libers  associate  the  activi- 
ties of  different  regions.  For  instance,  an  unsuspected  blow  upon 
the  hand  is  followed  instantly  by  a  drawing  back  of  the  hand  and 
arm;  most  of  the  muscles  of  the  upper  extremity  will  have  been 
called  into  action;  in  other  words,  many  motor  cells  (in  the  lower 
cervical  region  of  the  cord)  have  been  stimulated  to  a  sudden  lib- 
eration of  energy,  showing  the  effect  of  one  stimulus  when  conducted 
by  connecting  fibers  to  many  cells. 

Walking  was  in  the  beginning  a  voluntary  act,  but  education  of 
the  centers  has  made  them  independent  and  it  has  become  reflex. 
So  with  piano-playing,  and  many  others. 

Tendon  reflex. — A  familiar  example  is  the  "knee  jerk"  or 
patellar  reflex.  This  may  be  elicited  by  striking  the  patellar  tendon 
when  partly  stretched.  The  impression  thus  produced,  quickly 
reaches  the  motor  cells  which  innervate  the  quadriceps  muscle, 
and  the  leg  is  slightly  extended.  (There  are  several  tendon 
reflexes.) 

Skin  reflex. — Irritation  of  the  sole  of  the  foot  causes  the  plantar 
muscles  to  contract  (a  plantar  reflex).  Scratching  the  skin  of  the 
side  of  the  abdomen  causes  contraction  of  abdominal  muscles 
{abdominal  reflex).     There  are  other  skin  reflexes. 

The  spinal  cord  also  contains  centers  for  controlling  the  tone 
of  vessel  walls  or  vascular  tone.  Also  for  stimulating  the  action  of 
secreting  glands,  and  for  muscle  action  of  viscera.  These  functions 
are  exercised  through  the  sympathetic  ganglia  with  which  it  is 
widely  connected. 

Finally,  it  contains  centers  which  influence  (or  control)  certain 
processes  of  nutrition — trophic  centers. 

It  appears  at  once  that  the  spinal  cord  is  able,  from  the  wide 
distribution  of  its  nerves,  to  provide  for  most  of  the  activities  of 
the  body. 

Taken  as  a  whole  it  may  be  regarded  as  a  great  common  center 
of  sensation  and  motion;  and  because  of  many  connecting  fibers 
running  upward,  downward,  and  transversely,  it  can  combine 
and  to  some  extent  regulate,  the  functions  of  many  different  parts 
so  that  systematic  groups  of  movement,  or  series  of  movements,  may 
be  executed  by  organs  more  or  less  distant  in  the  body. 

In  other  words,  the  spinal  cord  can  to  some  extent  coordinate 
the  functions  of  the  spinal  nerves  and  skeletal  muscles. 


248  ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 

To  repeat  the  functions  of  the  spinal  cord,  they  are  to  preside 
over: 

1.  Reflex  action. 

2.  Muscle  tone. 

3.  Vessel  tone. 

4.  The  action  of  secreting  glands. 

5.  Nutrition  (trophic  action). 

These  may  all  be  exercised  independently  by  cells  in  the  anterior 
horns  and  their  nerve  connections.  (Other  functions  will  be 
mentioned  in  connection  with  those  of  the  brain.) 

The  function  of  the  spinal  nerves  is  to  connect  all  parts  of  the 
body  (except  face,  chin  and  anterior  part  of  head)  with  the  spinal 
cord,  for  the  purpose  of  conducting  sensory  and  motor  impulses  to 
and  from  the  cord. 

In  referring  to  motor  nerves  we  have  thus  far  mentioned  their 
natural  stimulus  only,  that  is, — the  impulse  generated  by  a  motor  ^ 
cell.  The  electric  current  applied  to  a  motor  nerve  in  any  part 
of  its  course  will  excite  its  activity,  showing  in  muscle  contraction, 
etc.  This  is  an  artificial  stimulus,  and  the  most  powerful  one 
known. 

(The  special  functions  of  individual  nerves  have  already  been, 
considered  in  foregoing  pages.) 


CHAPTER  XVIII. 

THE  BRAIN  AND  CRANIAL  NERVES. 

The  cerebro-spinal  or  central  nerve  system  comprises  the 
Brain  and  Spinal  Cord  with  their  nerves.  The  spinal  cord  and 
its  nerves  are  already  described  in  Chapters  XVI  and  XVII. 

The  brain^  is  ovoid  in  shape,  composed  of  gray  cells  and  white 
fibers,  situated  within  the  cranial  cavity  and  continuous  through 
the  foramen  magnum  with  the  spinal  cord. 


¥io.  z-]-]. — The  External  Surface  of  the  Brain  (Deaver). 

The  surface  consists  of  gray  cells  and  their  branches  and  is 
called  the  cortex  of  the  brain,  while  the  interior  is  white,  with  several 
ganglia  (collections  of  "gray  matter")  imbedded  within  it. 

The  surface  or  cortex  of  a  well-developed  brain  is  marked  by 
many  fissures,  separating  curved  ridges  called  convolutions  (or 
gyres),  the  number  and  depth  of  which  correspond  with  the  degree 

'  A  review  of  pages  229  and  230  is  recommended  before  studying  the  description 
the  brain. 

249 


250 


ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 


of  development,  the  brain  of  a  new-born  child  being  comparatively 
smooth. 

The  white  portion  is  composed  of  white  fibers  (the  medullated 
axons  of  the  cell  bodies).  They  run  in  many  directions.  Some 
connect  the  different  main  divisions  of  the  brain;  others  run  from 
one  part  of  the  cortex  to  another;  others  still,  in  great  number,  connect 
the  brain  and  spinal  cord  (Fig.  178).  Taken  together,  they  make 
up  the  mass  of  the  brain  itself.  '        ' 


Fig.  178. 
The  letters  mark  the  white  fibers.     They  connect  the  cortex  with  other  parts,  also 
different  parts  of  cortex  together.     Many  fibers  are  seen  to  pass  through  the  basal 
ganglia.     The  Roman  numerals  indicate  nerves  (Brubaker,  after  Starr). 


The  white  fibers  (Fig.  178)  connect  the  cortex  with  the  spinal 
cord;  some  connect  diilerent  parts  of  the  brain  together.  Taken 
together  they  compose  the  bulk  of  the  brain,  as  already  stated. 

The  brain  has  four  principal  parts,  the  cerebrum,  cerebellum, 
medulla  oblongata,  and  pons  Varolii. 

The  cerebrum  is  the  largest  division  and  occupies  nearly  the 
whole  cranial  vault.  It  is  divided  into  two  hemispheres,  right  and 
left,  by  a  longitudinal  fissure.  At  the  bottom  of  this  fissure  white 
fibers  are  seen  to  pass  from  one  side  to  the  other,  thus  forming  a 


THE    BRAIN. 


251 


transverse  commissure,  connecting  the  hemispheres,  and  called  the 
corpus  callosum  (Fig.  179).  Each  hemisphere  is  marked  off  by 
specially  deep  fissures,  into  lobes,  the  principal  ones  being  the 
frontal,  parietal,  occipital,  and  temporal.  The  principal  fissures 
between  the  lobes  are:  the  fissure  of  Rolando  between  the  frontal 
and  parietal;  the  parieto-occipital,  between  the  parietal  and  occipital; 
and  iYvQ  fissure  of  Sylvius,  between  the  temporal  lobe  below  and  the 
frontal  and  parietal  above  it. 

Important  note. — The  fissure  of  Rolando  is  often  called  the  central  fissure,  and 
the  convolutions  in  front  of  and  behind  it,  are  called  the  central  convolutions 
(anterior  and  posterior). 


Fig.  179. — Median  Surface  of  a  Hemisphere,  sii<j\vi.\(;  Third  and  Fourth 
\'entricles;  also  the  Corpus  Callosum  Divided,  and  the  Structltre  of  the 
Cerebellum  with  the  Pons  in  Front  of  It.  The  Pituitary  Body  is  Suspended 
from  the  Floor  of  the  Third  Ventricle  (Deaver). 

Within  the  white  substance  of  the  hemispheres  are  the  largest 
ganglia  in  the  brain,  and  since  they  are  situated  near  the  base, 
they  are  called  basal  ganglia.  They  are  the  optic  thalamus,  the 
lentiform  nucleus,  and  the  caudate  nucleus  (Fig.  181).  The  white 
matter  between  the  optic  thalamus  and  the  other  two,  constitutes 
the  internal  capsule.  Here  are  the  fibers  which  connect  centers  in 
the  cortex  with  those  in  the  spinal  cord;  hence  the  great  importance 
of  the  internal  capsule. 

The  hemispheres  are  not  solid,  but  each  encloses  a  cavity 
called  the  lateral  ventricle,  shaped  like  the  italic  letter  /  with  a 
projecting  arm  (laterally  and  downward).     The  extremities  of  the 


252 


ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 


ventricle  are  called  horns;  the  anterior  horn  being  in  the  frontal  lobe, 
the  posterior  horn  in  the  occipital,  and  the  lateral  or  descending  horn 
in  the  temporal  lobe.  The  great  ganglia  of  the  brain  are  in  the 
floor  of  the  lateral  ventricles  (hence  called  hasal  ganglia). 

The  lateral  ventricles  are  named 
like  the  hemispheres— r^'^/?/  and  left. 

There  are  certain  other  basal  ganglia 
which  are  important,  although  smaller  in 


The  cerebellum,  or  little  brain, 
also  consists  of  white  matter  covered 
with  gray.  It  has  two  hemispheres 
(situated  in  the  cerebellar  fossae  of 
the  occipital  bone)  which  are  not 
definitely  separated  like  the  hemi- 
spheres of  the  cerebrum,  but  are 
connected  by  a  median  portion  called 
the  vermis,  or  worm.  The  convolu- 
tions are  but  slightly  curved  and  are 
called  ridges,  and  the  furrows  (or 
sulci)  are  very  deep ;  a  section  shows 
that  they  are  so  arranged  as  to  re- 
semble the  branches  of  the  tree  called 
arbor  vitcz  (Fig.  179). 

The  medulla  oblongata,  although 
situated  within  the  cranium  (in  front 
of   the    foramen   magnum),    is    the 


Fig.  180. — ^PoNS  and  Medulla, 
Anterior  Surface. 
I,  2,  3,  Structures  belonging  to 
cerebrum;  4,  crura  of  cerebrum;  5, 
pons  Varolii;  9,  10,  11, 13,  14,  lateral 
surface  and  membranes  of  medulla; 
7,  pyramid;  8,  decussation  of  pyra- 
mids; 12,  anterior  median  fissure; 
13-27,  cranial  nerves;  28,  29,  ist 
and  2d  spinal  nerves  (Holden). 


upper  enlarged  portion  of  the  spinal 
cord  and,  like  it,  is  white  externally  and  gray  within. 

Its  anterior  columns  are  called  the  pyramids  (or  pyramidal  tracts) , 
and  consist  of  motor  fibers  passing  downward  from  the  brain.  Most 
of  the  fibers  of  each  pyramid  cross  to  the  opposite  side,  appearing 
to  interlace  in  the  median  fissure  (the  decussation  of  the  pyramids) , 
going  to  form  the  crossed  pyramidal  tracts;  the  others  pass  downward 
first  (as  the  direct  pyramidal  tract)  and  cross,  a  few  at  a  time,  at 
lower  levels  in  the  cord.  Thus  it  is  that  motor  fibers  coming  from 
one  side  of  the  brain  pass  to  the  other  side  of  the  cord,  and  this  is 
the  explanation  of  paralysis  of  one  side  of  the  body,  following  injuries, 
of  the  other  side  of  the  brain. 


VENTRICLES    OF    THE    BR-^IN.  253 

The  posterior  columns  of  the  medulla  contain  sensory  fibers 
going  upward  to  the  brain,  while  the  lateral  tracts  contain  both  motor 
and  sensory  fibers  (like  the  cord).  Most  of  the  sensory  fibers  also 
cross  at  different  levels. 

The  medulla  contains  centers  for  the  most  important  nerves  of 
the  body — respiratory:  cardiac,  vaso-motor,  et  al. 

The  pons  Varolii,  or  bridge  of  Varolius,  is  situated  in  front  of 
the  medulla,  below  the  cerebrum  and  cerebellum,  and  so  named 
because  fibers  run  through  it  from  all  three  of  the  other  parts  of 
the  brain,  as  though  it  were  a  bridge  between  them.  It,  also,  is 
white  externally  and  gray  within,  and  is  not  unlike  the  cord,  although 
in  a  still  more  modified  form  than  the  medulla. 

Two  large  nerve  bundles  are  seen  diverging  from  the  anterior  border  of  the 
pons,  the  crura  of  the  cerebrum  (often  called  peduncles) .  They  contain  all  of  the 
motor  and  sensory  fibers  of  the  cerebrum  which  pass  through  the  pons,  to  or 
from  the  cord.  The  fibers  to  and  from  the  cerebellum  form  peduncles  of  the 
cerebellum  smaller  in  size. 

THE  FIVE  VENTRICLES  OF  THE  BRAIN  (Fig.  i8i). 

The  five  ventricles  are  different  portions  of  one  cavity,  which  is 
continuous  with  the  central  canal  of  the  spinal  cord.  The  two 
lateral  ventricles  have  been  mentioned.  The  third  ventricle  is 
between  them,  and  the  fourth  ventricle  is  behind  the  third,  being 
in  the  medulla  and  pons;  some  of  the  most  important  nuclei  or 
centers  of  the  body  are  imbedded  in  the  floor  of  the  fourth  ventricle. 

Each  lateral  ventricle  communicates  with  the  third  through  an 
opening  called  the  foramen  of  Mnnro;  the  third  communicates  with 
the  fourth  through  the  aqueduct  of  the  cerebrum  (aqueduct  of  Sylvius) , 
a  slender  canal  in  the  crura  and  pons;  and  the  fourth  ends  in  the 
central  canal  of  the  cord.  These  spaces  are  therefore  continuous, 
and  they  contain  cerebrospinal  fluid. 

The  so-called  fifth  ventricle  is  not  a  portion  of  the  general  cavity — not  a  true 
ventricle.     It  is  a  narrow  space  in  front  of  the  third,  having  no  opening  whatever. 

Clinical  note. — Hydrocephalus  is  caused  by  an  accumulation  of  fluid  in  the 
ventricles,  enlarging  them  and  pressing  upon  the  brain  substance,  and  conse- 
quently upon  the  bones  of  the  skull.  It  is  very  likely  to  occur  in  children  who 
have  rachitis,  or  "rickets." 

A  similarity  in  structure  and  arrangement  of  parts  is  plainly  evident  in 
the  brain  and  spinal  cord.     Recall  the  cord — a  collection  of  nerve  fibers. 


254  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

the  greater  number  running  up  or  down,  but  with  many  passing  from  one 
side  to  the  other;  a  central  canal  surrounded  by  collections  of  "gray  matter"; 
two  lateral  halves  connected  by  transverse  commissural  fibers. 

These  parts  may  all  be  traced  in  the  brain.     The  central  canal  extends 
through  the  medulla  and  pons  into  the  cerebrum,  expanding  into  a  general 


Fig.  i8i. — The  Ventricles,  showing  Basal  Ganglia  in  the  Floor  of  the  Lateral 
Ventricles  (Hirschfeld  and  Leveille). 
a.  Anterior  portion  of  corpus  callosum;  h,  caudate  nucleus;  c,  location  of  lentiform 
nucleus;  d,  optic  thalamus;  h,  i,  quadrigeminal  bodies;  g,  third  ventricle;  o,  fourth 
ventricle ;  p,  medulla.     The  fifth  ventricle  is  in  front  of  e. 

ventricular  cavity.  Gray  matter  (ganglia)  lies  close  to  this  canal,  even  pro- 
jecting into  it.  The  white  fibers  are  here,  but  they  diverge  on  every  side,  and 
many  take  new  directions;  also  the  halves  of  the  brain  are  connected  by 
transverse  (commissural)  fibers  (the  corpus  callosum).  The  brain  has  one 
part  not  found  in  the  cord  (and  a  most  important  part),  viz.,  a  covering  of 
"gray  matter,"  or  cortex. 

THE  MEMBRANES  OF  THE  BRAIN. 

These  are  three  in  number,  the  pia  mater,  arachnoid,  and  dura 
mater,  like  those  of  the  cord,  and  continuous  v^ith  them. 

The  pia  mater  fits  closely  to  the  brain,  following  all  convolu- 
tions and  uneven  surfaces;  it  is  necessary  to  the  life  of  the  brain,  as 


THE    CRANIAL    NERVES.  255 

periosteum  is  to  bone,  and  for  the  same  reason — it  bears  the  blood- 
vessels which  nourish  it. 

The  arachnoid  lies  close  to  the  pia  but  stretches  across  the 
furrows,  leaving  subarachnoid  spaces  for  cerebro-spinal  fluid  as  in 
the  spinal  cord.  The  largest  spaces  are  at  the  base  of  the  brain 
where  the  greatest  irregularities  of  surface  are  found. 

The  dura,  firm,  white  and  tough,  covers  the  others  loosely  and 
lines  the  entire  skull,  taking  the  place  of  periosteum.  It  has  a 
number  of  meningeal  arteries  branching  in  its  substance,  for  its 
own  nourishment  and  the  nourishment  of  the  skull  bones  (since  it 
is  their  internal  periosteum).  It  sends  layers  between  the  large 
divisions  of  the  brain — one  between  the  hemispheres  of  the  cerebrum 
is  called  the  falx  cerebri,  and  one  stretched  over  the  cerebellum  is 
called  the  tentorium  cerebeUi.  They  support  the  weight  of  portions 
of  the  brain  in  different  positions  of  the  head. 

The  dura  also  presents  several  large  veins  called  sinuses  which 
collect  the  blood  from  the  brain.  The  largest  are  the  sagittal 
{longitudinal)  running  from  front  to  back  in  the  median  line,  and 
the  two  transverse  sinuses  (lateral)  right  and  left  which  end  in  the 
internal  jugular  vein  at  the  jugular  foramen. 

Surgical  note. — The  transverse  or  lateral  sinus  lies  partly  in  a  deep  groove 
on  the  mastoid  bone  {sigmoid  groove)  and  this  adds  to  the  gravity  of  operations  in 
the  mastoid  region. 

Clinical  note. — Inflammation  of  the  membranes  is  meningitis.  When 
affecting  the  dura  it  is  pachymeningitis;  when  it  is  of  the  pia  and  arachnoid, 
it  is  leptomeningitis. 


THE  CRANIAL  NERVES. 

There  are  12  pairs  of  cranial  nerves.  They  are  seen  at  the 
base  of  the  brain  and  leave  the  skull  through  various  foramina  in 
the  cranial  bones.  Some  are  nerves  of  motion,  some  of  sensation 
and  some  are  mixed  (Fig.  182).     They  are  named  as  follows: 

1.  Olfactory.  7.  Facial. 

2.  Optic.  8.  Acoustic  or  auditory. 

3.  Oculo-motor.  g.  Glosso-pharyngeal. 

4.  Troclear,  or  pulley  nerve.  10.  Vagus,  or  pneumo gastric.  ' 

5.  Trifacial,  or  trigeminus.  11.  Spinal  accessory. 

6.  Abducens.  12.  Hypoglossal. 


256 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


The  first,  or  olfactory  (Fig.  182),  is  the  nerve  of  smell.  Being 
sensory  it  is  traced  toward  the  brain. 

Minute  nerves  from  the  upper  part  of  the  nasal  mucous  membrane  {olfactory 
region),  pass  up  through  the  sieve-Uke  plate  of  the  ethmoid  bone  and  enter  the 
olfactory  bulb;  from  the  bulb  proceeding  in  a  soft  band  of  fibers  called  the 
olfactory  tract,  to  the  brain,  most  of  them  finally  reaching  the  temporal  lobe,  "where 
they  end  in  the  center  for  the  sense  of  smell,  or  olfactory  center. 


First,  olfactory 


—   Second,  optic 


Third,  oculo-motor 
Fourth,  pathetic 

Fifth,  trifacial 
Sixth,  abducens 
Seventh,  facial 
Eighth,  auditory 

Ninth,  glosso-pharynxal 

Tenth,  vagus 

Eleventh,  spinal  accessory 


Twelfth,  hypoglossal 


J^iO^ 


Fig.  182. 


-Base  of  Beain  and  Cranial  Nerves,  showing  Relation  of  the  Pons, 
Medulla,  and  Cerebrltm  (Monat  and  Doyen;  Brubaker). 


The  second,  or  optic  (Fig.  183),  is  the  nerve  of  vision.  It 
begins  in  the  retina. 

The  retinal  fibers  are  gathered  to  form  the  nerve,  which  passes  through  the 
optic  foramen  into  the  cranial  cavity.  The  two  optic  nerves  meet  above  the 
body  of  the  sphenoid  bone,  and  most  of  the  fibers  cross  each  other  there,  forming 
the  optic  commissure  (or  chiasm),  and  then  proceed  to  the  occipital  lobes,  where 
they  end  in  the  visual  centers.     (Fig.  180,  16,  optic  chiasm.) 

The  third,  or  oculo-motor  (Fig,  183),  is  the  mover  of  the  eyes. 
It  proceeds  from  the  base  of  the  brain  and  enters  the  orbit,  to  sup- 
ply four  of  the  muscles  of  the  eyeball,  and  also  the  elevator  of  the 
upper  lid.  (Eye  muscles  thus  supplied:  Superior,  inferior,  and 
internal  recti,  and  inferior  oblique.) 


CRANIAL   NERVES. 


257 


6   7         to 

Fig.  183. — Nerves  of  the  Orbit. 
I,  Optic  nerve;  2,  Oculo-motor  (3d);  5,  ab- 
ducens    (6th).       Other    figures    mark    various 
branches.     10,  Ciliary  ganglion  (Sappey). 


By  the  action  of  the  first  three  the  eye  is  turned  upward,  downward  and 
outward;  the  inferior  oblique  turns  it  upward  and  outward. 

The  third  nerve  supplies 
also  the  circular  fibers  of  the 
iris  which  contract  the  pupil 
of  the  eye,  and  the  accom- 
modation muscle — by  which 
the  eye  is  focused  for  view- 
ing objects  at  different  dis- 
tances. 

The  fourth,  or  trochlear 
nerve,  is  so  called  because 
it  supplies  the  muscle  which 
rolls  the  eye  downward  and 
outward  ( the  superior 
oblique  muscle;  the  tendon  passes  through  a  loop  and  bends  around 
like  the  rope  on  a  pulley  or  trochlea). 

The  fifth,  or  trifacial  (trigeminal),  is  the  great  sensory  nerve 

of  the  face,  nose  and  throat. 
Some  motor  fibers  for  muscles 
of  mastication  accompany  the 
sensory  fibers  and  thus  there 
are  said  to  be  two  roots;  sen- 
sory and  motor. 

The  sensory  root  has  a  large 
ganglion,  semilunar  (or  Gasserian) 
ganglion,  and  in  front  of  this  it  is 
in  three  divisions,  called  the  oph- 
thalmic, maxillary,  and  mandibular 
nerves.     The  ophthalmic  nerve  lies 
in  the  orbit;  it  is  the  nerve  of  sen- 
sation of  the  structures  contained 
therein;  also  of  the  eyelids  and  side 
of  the  nose.     The  maxillary  nerve 
appears  at  the  infraorbital  foramen. 
It  is  the  nerve  of  sensation  for  the 
upper    teeth    and   the   cheek   and 
temple.     The  mandibular  nerve  is 
in  the  infratemporal  fossa,  and  is  the  nerve  of  sensation  for  the  lower  teeth 
and  structures  of  the  lower  jaw.     The  motor  root  joins  this  branch  to  supply  the 
muscles  of  mastication. 
17 


Fig.  184. — The  Distribution  of  the  Three 
Divisions  of  the  Fifth  Nerve  (Leidy). 


258 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


The  nerve  of  the  sense  of  taste,  called  the  lingual  (or  gustatory),  accompanies 
the  mandibular  nerve  from  the  anterior  two-thirds  of  the  tongue. 

Surgical  notes. — Facial  neuralgia  is  sometimes  so  severe  and  intractable 
that  the  semilunar  ganglion  is  removed  by  the  surgeon.  This  interferes  with, 
sensation  of  the  face,  but  not  with  motion. 

Three  sensitive  points  on  the  face  where  three  sensory  branches  of  the  tri- 
facial pass  through  foramina:  the  supraorbital  foramen,  for  the  supraorbital 
branch  of  the  ophthalmic;  the  infraorbital  foramen  for  the  infraorbital  branch. 

of  the  maxillary;  the  mental  for- 
amen for  the  mental  branch  of  the 
mandibular.  Section  of  these 
nerves  is  sometimes  done  for 
facial  neuralgia. 

The  sixth,  or  abducens, 
is  a  motor  nerve,  supplying 
the  external  rectus  muscle, 
which  turns  the  eye  outward, 
or  abducts  it. 

The  seventh,  or  facial 
(Fig.  185),  is  a  motor  nerve. 
It  passes  through  the  channel 
in  the  petrous  bone  called 
the  facial  or  Fallopian  canal ^ 
(which  brings  it  close  to  the 
middle  ear).  Emerging  from 
the  skull  it  passes  forward, 
through  the  parotid  gland,  and  divides  into  many  branches  supply- 
ing all  the  muscles  of  expression. 

Clinical  note. — If  this  nerve  is  paralyzed,  the  side  of  the  face  supplied  by  the 
injured  nerve  droops  and  is  useless,  and  the  eye  fails  to  close.  The  face  will  ' 
be  drawn  toward  the  un-m]uxed  side  by  the  opposite  nerve;  this  is  plainly  seen, 
if  the  patiejit  smiles,  or  attempts  to  whistle. 

The  eighth,  or  auditory  (acoustic),  is  a  sensory  nerve.  It  has 
two  portions — the  cochlear,  or  proper  nerve  of  hearing,  and  the 
vestibular,  or  nerve  of  equilibration.  Both  pass  from  the  internal  ear 
through  the  internal  auditory  canal  to  the  medulla.  (See  page  275, 
Nerves  of  the  Internal  Ear.) 

The  ninth,  or  glosso-pharyngeal,  is  a  mixed  nerve.  The  motor 
fibers  pass  from  the  medulla  through  the  jugular  foramen  and. 
supply  the  muscles  of  the  tongue  and  pharynx,  as  its  name  suggests.. 


Fig.  185. 

The  figures  mark  the  branches  of  the 

seventh  or  facial  nerve  (Hold en). 


THE    VAGUS    NERVE. 


259 


The  sensory  fibers  convey  sensations  of  taste  from  the  tip  and  back 
part  of  the  tongue.  Bitter  things  are  especially  appreciated  by  the 
glosso-pharyngeal. 

The  tenth,  or  vagus  (pneumogastric),  is  a  mixed  nerve.  It  is 
traced  from  the  medulla  through  the  jugular  foramen. 

Branches. — Laryngeal  to  larynx;  pharyngeal  to  pharynx,  cardiac 
to  the  heart;  pulmonary  to  the  lungs,  and  others,  indirectly,  to  the 
stomach,  liver,  spleen,  and  intestines. 

It  regulates  the  action  of  the  heart  and  the  act  of  swallowing; 
it  is  the  sensory  nerve  of  the  air  passages  from  the  larynx  down,  and 
of  the  alimentary  tract  from  the  pharynx  down. 

The  eleventh,  or  spinal  accessory,  is  traced  from  the  medulla 
through  the  jugular  foramen,  with  the  ninth  and  tenth.  It  supplies 
the  sterno-mastoid  and  trapezius  muscles  with  motor  nerves.  (A 
portion  of  it  is  accessory  to  the  vagus.) 

The  twelfth,  or  hypo-glossal  (under  the  tongue),  supplies  the 
muscles  of  the  tongue  and  those  connecting  it  with  the  jaw  and 
hyoid  bone;  also  the  ribbon  muscles  in  front  of  the  neck  (page  86). 

Summary. 
The  nerves  of  the  cerebro-spinal  system  are  distributed  to 
all  voluntary  muscles,  and  to  all  sensitive  structures,  as  skin,  mucous 
membranes,  lining  of  joints,  and  periosteum.     They  are  the  nerves 
of  conscious  life. 

CRANIAL  NERVE  SUPPLY  TO  CERTAIN  MUSCLE  GROUPS. 


Region. 

Muscles. 

Name. 

Head 

Of  scalp  and  face. 

Facial,  or  7th. 

Of  tongue, 

Hypo-glossal,  or  12  th. 

Of  mastication — temporal. 

masseter, 

buccinator, 

two  pterygoids, 

Trigeminal,  or  5th. 

The  digastric  assists  in  mastica- 

tion, 

5th  and  7th. 

Of  the  orbit — inferior  oblique, 

levator  palpebrae, 

superior  rectus, 

inferior  rectus. 

internal  rectus. 

Oculo-motor,  or  3d. 

external  rectus, 

Abducens,  or  6th. 

superior  oblique, 

Trochlear,  or  4th. 

Neck,  lateral 

Sterno-mastoid. 
Trapezius, 

Neck,  posterior 

Accessory,  or  nth. 

Neck,  anterior 

Below  the  chin,  also  tongue, 

Ilypo-glossal,  or  12  th. 

Pharynx, 

Larynx, 

Esophagus 

Vagus,  or  loth. 

Pharynx  and  Larynx 

Have  also  fibers  from. 

Glosso-pharyngeal,  or  9th, 

26o  ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 

FUNCTIONS   OR  PHYSIOLOGY  OF  THE  BRAIN 
AND   CRANIAL  NERVES. 

The  cerebrum  presides  over  all  conscious  acts,  and  recognizes 
all  sensations.  The  anterior  portion  of  the  frontal  lobes  is  said 
to  be  the  region  of  mental  activity  or  the  seat  of  the  intellect. 

Cerebral  Localizations. — Connections  between  cortical  areas 
and  certain  parts  of  the  body  have  been  noted,  and  their  control 
over  those  parts  has  been  demonstrated  (Figs.  i86,  187).  Among 
them  are  the  centers  for  face  muscles  and  for  the  upper  extremity,  in 


GONCRtTE   CONCEPT 


Fig.    186. — The    Areas    and  Centers  of  the  Lateral  Aspect  of  the  Human 
Hemicerebrum  (C.  K.  Mills). 

the  anterior  central  convolution;  the  centers  for  speech  muscles  in  the 
lower  convolutions  of  the  frontal  lobe.  (Broca's  convolution  is  the  third 
left  frontal.)  Likewise  the  centers  for  the  special  senses  are  fairly 
well  known — as  for  vision  and  memory  in  the  occipital  lobe;  for 
taste  in  temporal;  for  touch  in  the  parietal;  and  for  hearing  and  smell 
in  the  temporal  snad  frontal. 

The  function  of  the  cerebellum  is  to  associate  or  coordinate  the 
actions  of  muscle-groups  for  the  accurate  performance  of  special 
movements.  This  is  most  conspicuously  shown  in  maintaining  the 
equilibrium  of  the  body,  whether  standing  or  walking.  Injury  to 
the  cerebellum  results  therefore  in  vertigo  and  dizziness,  in  loss  of 


THE   MEDULLA    OBLONGATA. 


261 


the  power  to  keep  one's  balance,  and  of  the  ability  to  walk  without 
staggering. 

The  medulla  oblongata  contains  many  important  governing 
centers.  Among  them,  are  those  for  the  organs  of  circulation  and 
respiration;  these  are  situated  near  each  other  and  constitute  the 
"vital  knot."  Consequently  this  part  of  the  nerve  system  presides 
over  processes  of  the  body  which  are  necessary  to  life  itself,  and 
when  one  remembers  that  the   motor  and  sensory  fibers  which 


Fig.  187. 


-The  Areas  and  Centers   of  the  Mesial  Aspect   of  the   Human 
Hemicerebrum  (C.  K.  Mills). 


connect  the  brain  and  cord  all  pass  through  the  medulla,  it  is  easy 
to  understand  that  injury  here  produces  far-reaching  results. 

The  pons  varolii  is  associated  with  the  medulla  in  its  cranial 
nerve  connections;  most  of  its  fibers  are  conducting  paths  between 
the  other  parts  in  the  cranial  cavity. 

The  function  of  the  cranial  nerves  is  to  connect  parts  of 
the  head  and  face,  also  certain  muscles  of  the  neck,  with  the  brain. 
Through  the  vagus  (or  pncumogastric)  nerve — the  heart,  lungs 
and  digestive  organs  possess  cranial  connections. 


CHAPTER  XIX. 

THE  SYMPATHETIC  DIVISION  OF  THE  NERVE 
SYSTEM. 

"We  have  thus  far  considered  those  nerve  actions  which  are 
associated  with  consciousness.  Although  some  may  be  performed 
in  a  purely  reflex  manner,  all  may  be  exercised  voluntarily. 

The  Symphathetic  Division  is  concerned  with  involuntary 
processes  only.  Nerve  stimulus  between  the  central  nerve  system 
and  internal  organs,  and  to  all  involuntary  muscle  fibers,  is  con- 
veyed through  sympathetic  nerves. 

The  nerve  tissues  of  this  division  are  mostly  gray,  a  large  majority 
of  the  fibers  being  non-medullated.  This  division  of  the  nerve 
system  consists  of  many  ganglia  connected  together  with  nerve 
trunks,  and  of  nerves  which  connect  the  ganglia  with  various  organs. 
They  also  communicate  freely  with  the  cerebro-spinal  division. 

About  twenty-two  pairs  of  sympathetic  ganglia  are  arranged  in 
two  chains  situated  within  the  body,  at  the  sides  of  the  vertebrae,  and 
connected  below  in  front  of  the  coccyx.  These  are  the  vertebral 
ganglia  (Fig.  i88). 

(Others  are  situated  in  the  head  and  the  cavities  of  the  body — 
thoracic,  abdominal  and  pelvic;  these  are  intimately  connected  with 
the  viscera  contained  therein.) 

The  vertebral  ganglia  are  named  according  to  their  location. 
They  are  cervical,  thoracic,  lumbar,  sacral  and  coccygeal.  They 
all  receive  communicating  branches  from  spinal  nerves. 

The  branches  or  nerves  from  these  various  ganglia  interlace  in  close 
networks  forming  plexuses,  which  follow  the  course  of  arteries, 
supplying  their  walls  and  the  viscera  to  which  they  run.  They  also 
supply  the  cells  of  glands. 

Special  branches  from  cervical  ganglia  accompany  arteries  to  the 
head,  larynx,  pharynx,  thyroid  body,  and  heart. 

Special  branches  from  thoracic  ganglia  accompany  arteries  to 
lungs  and  esophagus  in  the  thorax;  stomach,  liver,  spleen,  and 
other  viscera  in  the  abdomen.     (The  branches  passing  through  the 

262 


SYMPATHETIC    GANGLIA    (VERTEBRAL). 


263 


CERVICAL 
PLEXUS 


BRACHIAL 
PLEXUS 


accessory  nerve 


SUPERIOR  CERVICAL 
QANQLION  OF  SYM- 
PATHETIC 


MIDDLE   CERVI- 
CAL   GAN3LION 


NFERIOR   CERVI- 
CAL GANGLION 


LUMBAR    GANGLIA 


tUMBAR /LUMBAR^ 
PLEXUS    \  NERVES 


cocc 

PLEXUS 


Fig.  188.— Left  Sympathetic  Ganglia  showing   Communications  with  Spinal 

Nerves  (Testut). 


264  ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 

diaphragm  to  abdominal  viscera  are  called  splanchnic  nerves — three 
on  each  side.) 

Special  branches  from  lumbar  ganglia  accompany  arteries  to 
kidneys  and  pelvic  organs. 

Special  branches  (or  nerves)  from  the  sacral  ganglia  accompany 
arteries  to  the  pelvic  organs. 

The  most  important  plexuses  are  the  cardiac  and  the  pulmonary 
in  the  thorax,  the  celiac  (solar)  in  the  abdomen,  and  the  hypo-gastric 
in  the  pelvis  (Fig.  189). 

The  cardiac  plexus  lies  underneath  and  behind  the  arch  of  the 
aorta.  Its  branches  supply  the  heart  and  lungs,  following  the 
coronary  and  pulmonary  arteries. 

The  celiac  (or  solar)  plexus  is  in  the  abdomen,  in  front  of 
the  aorta,  at  the  beginning  of  the  celiac  artery.  It  contains  two 
large  ganglia — the  right  and  left  celiac  {semilunar)  ganglia.  This 
plexus  controls  the  vessels  and  muscular  coats  of  the  abdominal 
viscera;  it  has  been  called  the  abdominal  brain.  Thus  it  may  be 
understood  how  a  severe  blow  over  the  plexus  would  produce  a 
very  widespread  and  serious  result. 

The  hypo-gastric  plexus  is  in  front  of  the  fifth  lumbar  vertebra 
and  divides  to  form  the  right  and  left  pelvic  plexuses,  which  are 
distributed  to  all  of  the  pelvic  viscera  (along  with  branches  from 
the  sacral  ganglia  and  lumbar-spinal  nerves). 

Notes. — Cardiac  nerves  from  the  cervical  ganglia  descend  to  the  thorax, 
entering  the  cardiac  plexuses  and  supplying  the  heart  and  lungs.  Certain 
branches  from  the  thoracic  ganglia  form  splanchnic  nerves  which  des'cend  to  the 
abdomen,  entering  the  celiac  plexus  and  celiac  ganglia,  and  supplying  digestive 
organs.  Certain  nerves  from  the  lumbar  ganglia  descend  to  the  hypo-gastric 
plexus  to  enter  the  pelvic  plexuses,  supplying  pelvic  organs. 

FUNCTIONS  OR  PHYSIOLOGY  OF  THE  SYMPATHETIC 

NERVES. 

The  work  of  organs  supplied  with  sympathetic  nerves  is  per- 
formed involuntarily  and  unconsciously  save  in  its  results.  Visceral 
muscles,  secreting  cells,  vessel  walls,  are  all  under  the  immediate 
domain  of  the  sympathetic  ganglia  and  nerves,  whose  motor  and 
sensory  fibers  are  parts  of  the  great  nerve  system  of  the  body,  through 
communicating  branches. 

Certain  facts  indicate  a  communication  between  the  brain  and 
sympathetic  nerves,  for  instance :  the  thought  of  food  causes  a  flow 


SYMPATHETIC    PLEXUSES. 


265 


Cereieai  nerve 


flents abcutVertebnzl  ajf.-- 
Kaus aboatSuiclav'tan  art. 


Jhoracic  nerve    I 
H 


Otic  ^anytion 

■fions  with 
•o/orm  FA 

SubmaiUlarij  ganglion 


Connections  loif/i  Va^us  4  Glonophajyn^al 
fyybrm  F/iari/nyeal  /?/exas. 


.Superior'      j 

.Middle     \Carriiac  nerves 


,InJeriur\ 

\  <  Connections  ivitk  Va^us  and 

■  \      ,''',  /ie  cur  rent  lart/nycal . 


>  Xeft Fulmonari/  plexus 
CARDIAC  PLEKUS 


•all  IH^ — V-      7 

\Smcdlest\      "'■'inUlrcroci   ,,wgmfflca   y-Diaphra^m 
;     i  J  ^-Phrenic  ^fhrj^^^Z^.^ il______^ 

^palic  p/exus 


*'       Autrbacm 

'-fleiusesoj^  &  \ 

Meissner\ 


Aidominal  Aortic  pUiu* 


flYPOCASmiC  PLEXUS 


Coccygeal  nerve 


Gan^liori  CcKcycftum  impar 
Fig.  189.— Principal  Ganglia  and  Plexuses  of  the  Sympathetic  System  (Morris). 


266  ANATOMY   AND    PHYSIOLOGY   FOR   NURSES. 

of  saliva  {salivary  cells  are  stimulated — think  of  a  lemon).  Fright 
or  anxiety  may  inhibit  or  prevent  the  secretion  of  saliva;  or  inter- 
fere with  digestion  through  a  similar  effect  upon  other  digestive 
fluids;  and  it  is  well  known  that  the  secretion  of  milk  is  greatly 
modified  by  mental  or  emotional  influences. 

So  with  general  vaso-motor  action.  We  all  know  the  blanched 
face  of  fright  or  mental  shock;  the  flush  of  joyous  excitement;  or 
the  blush  of  embarrassment. 

Again  the  effect  of  vaso-motor  action  may  be  seen  when  intense 
cold  is  applied  to  the  skin.  The  cutaneous  vessels  contract,  the 
blood  is  driven  out,  the  skin  becomes  white.  The  opposite  condition 
is  caused  by  heat — the  vessels  dilate,  the  blood  flows  in  and  the 
skin  is  red. 

By  alternate  action  of  the  two  kinds  of  vaso-motor  nerves 
(vaso-dilators  and  vaso-constrictors) ,  the  blood-supply  is  adapted  to 
special  and  varying  needs  of  different  parts  of  the  body,  and  the 
balance  of  pressure  preserved  in  all  of  their  vessels. 

When  an  organ  has  work  to  perform  its  vessels  dilate  and  the 
necessary  blood  is  supplied.  When  the  work  is  finished  the  vessels 
return  to  their  usual  size  (their  vessel-tone  being  restored  by  vaso- 
constrictors). 

The  process  of  digestion,  for  example,  requires  that  there  should 
be  much  blood  in  many  organs;  the  same  is  true  of  general  muscular 
exercise.  Consequently,  to  exercise  violently  after  a  full  meaL  is  a 
mistake,  because  the  muscles  would  deprive  the  digestive  organs 
of  the  extra  blood  which  they  need,  and  an  attack  of  indigestion 
might  follow;  at  best,  digestion  would  be  delayed.  It  would  be 
better  to  delay  the  exercise. 

Many  examples  might  be  given  and  will  probably  occur  to  the 
mind  of  the  student,  of  the  interactions  of  different  parts  of  the 
sympathetic  system. 

These  are  the  processes  which  must  go  on  more  or  less  continu- 
ously. Some  may  be  suspended  temporarily,  as  gland  secretions,  or 
digestion,  or  the  formation  of  excretions,  but  they  never  entirely 
cease  without  causing  the  death  of  the  individual. 

Summary. 

The  sympathetic  nerves  supply  all  involuntary  muscles,  the 
coats  of  blood-vessels  and  the  cells  of  secreting  glands.     They  are 


PHYSIOLOGY    OF    THE    NERVE    SYSTEM.  267 

the  nerves  of  unconscious  life,  as  the  cerebrospinal  nerves  are  the 
nerves  of  voluntary  and  conscious  life. 

SUMMARY  OF  THE  FUNCTIONS  OF  THE  NERVE  SYSTEM 

AS  A  WHOLE. 

We  have  now  concluded  the  study  (briefly)  of  the  entire  nerve 
system,  and  we  have  seen  how  intimately  its  various  parts  are  con- 
nected. Only  through  a  knowledge  of  these  connections  can  the 
functions  of  the  system  be  understood. 

Different  parts  of  the  spinal  cord  are  associated  one  with  another 
"by  conduction  fibers,  and  the  cord  is  connected  with  the  hrain  above 
"by  many  more,  running  upward  or  downward  through  the  medulla 
and  pons.  (On  the  inferior  surface  of  the  brain  we  see  these  fibers 
as  crura  or  penduncles,  disappearing  in  the  substance  of  the  cerebrum 
and  cerebellum;  they  are  finally  connected  with  the  gray  cells  of  the 
cortex.) 

In  the  spinal  cord  and  its  nerves  we  find  the  apparatus  for  reflex 
action  which  appears  in  so  many  phases — as  muscle  contraction, 
muscle-tone,  vessel  tone,  etc.  The  spinal  cord,  then,  is  a  great 
reflex  center,  a  conducting  pathway,  and  an  organ  of  coordination  of 
■skeletal  muscles. 

Included  in  the  medulla  are  centers  for  still  more  important 
reflexes:  the  respiratory  center;  the  cardio-vascular  center  or  center 
for  heart-action  and  vessel-tone  combined;  the  heat  regulati.ig 
center;  deglutition  center,  and  others.  Certain  of  these  may  be 
modified  by  the  will;  for  example,  the  respiratory  act — we  may 
take  a  long  full  breath  or  a  short  and  shallow  one;  breathe  rapidly 
or  slowly,  at  will.  Deglutition  is  still  nearer  to  the  realm  of  voluntary 
movements — only  when  food  reaches  the  esophagus,  is  the  act  of 
deglutition  purely  reflex.  (Here  is  the  first  appearance  of  unstriped 
muscle  in  the  digestive  tract.) 

Going  higher  we  find  the  cerebellum  presiding  over  the  coordi- 
nation of  conscious  and  voluntary  movements,  through  its  connec- 
tion with  the  cortex  of  the  cerebrum  on  one  hand,  and  the  pons, 
medulla  and  cord  on  the  other.  Also  upon  the  cerebellum  depends 
the  maintenance  of  body  equilibrium.  For  this  it  is  necessary  that 
the  semicircular  canals  of  the  internal  ear  should  be  normal  and  in 
perfect  connection  with  the  cerebellum.     Other  sensory  connections 


268 


ANATOMY   AND    PHYSIOLOGY    FOR   NURSES. 


Fig  190.— Diagram  Showing  the  Relation  oe  Skeletal,  Muscle  and  Nerve 
Tissues  (G.  Bachman).  f.a.  Bones  of  the  forearm  representing  the  skeletal  tissue;  e.y. 
the  elbow  joint,  the  fulcrum  of  the  lever  formed  by  the  bones  of  the  forearm;  W_.  a 
weight  acting  in  a  downward  direction  and  representing  the  passive  force  of  gravi_ty|^ 
sk  m.  a  skeletal  muscle  acting  in  an  upward  direction  and  the  source  of  the  active 
power  to  be  applied  to  the  lever;  sp.c.  transection  of  the  spinal  cord  showing  the  relation 
of  the  white  and  the  gray  matter:  m.c.  a  motor  cell  in  the  anterior  horn  of  the  gray 
matter;  ef.n.  an  efferent  nerve-fiber  connecting  the  motor  cell  from  which  it  arises  with 
the  skeletal  muscle  and  contained  in  the  ventral  roots  of  the  spinal  nerves;  aj.n.  an 
afferent  nerve-fiber  arising  from  the  ganglion  cell  along  its  course  and  connecting  the 
skin,  5.,  on  the  one  hand  with  the  spinal  cord  on  the  other  hand  and  contained  in  the 
dorsal  roots  of  the  nerves;  c.s.c.  coronal  section  of  the  cerebrum  showing  the  relation 
of  the  gray  to  the  white  matter;  v.c.  a  volitional  or  motor  cell;  i.a.  a  descending  axon 


PHYSIOLOGY    OF    THE    NERVE    SYSTEM.  269 

also  contribute  to  the  exercise  of  this  function;  for  example,  to  walk 
unaided  without  vision  is  possible,  but  not  in  a  straight  line;  or,  to 
walk  with  feet  benumbed  is  difficult,  more  so  to  stand  motionless; 
showing  that  the  cerebellum  is  stimulated  to  the  coordination  by 
which  equilibrium  is  maintained,  by  more  than  one  sort  of  stimulus, 
probably  by  many. 

Going  still  higher,  we  find  in  the  cerebrum  the  perfecting  of 
the  plan  for  bringing  the  whole  sentient  and  moving  organism  into 
the  domain  of  consciousness  and  the  will.  This  is  by  means  of 
the  connections  of  the  cerebrum  through  the  pons,  medulla,  and  cord 
and  their  nerves,  with  every  part  of  the  body  from  which  afferent 
impulses  and  to  which  efferent  impulses  may  be  transmitted  (Fig. 

190)- 

Concerning  the  reception  and  originating  of  ideas,  the  exercise 

of  thinking — in  other  words,  intellectual  processes — we  know 
nothing,  except  that  these  activities  certainly  depend  for  their  normal 
manifestation  upon  a  normal  cerebrum.  A  well-developed  cerebrum 
has  good  convolutions  and  deep  furrows.  These  indicate  mental 
power,  being  of  more  importance  than  the  mere  size  of  the  brain. 
The  brain  of  the  infant  possesses  all  of  the  interior  parts,  as  ganglia, 
etc.,  but  the  cortex  is  almost  smooth.  With  the  growth  of  the  child 
and  quickening  of  the  mind,  the  convolutions  and  furrows  appear 
and  develop. 

The  sympathetic  division  of  the  nerve  system  is  the  medium 
of  communication  (through  communicating  branches)  of  nerve 
impulses  between  the  cerebro-spinal  system  and  the  organs  con- 
cerned in  involuntary  processes  (notably  those  connected  with 
nutrition  and  growth)  through  control  of  secreting  cells  and  vessel- 
tone. 

or  nerve-fiber  connecting  the  volitional  cell  from  which  it  arises  with  the  motor  cell  in 
the  spinal  cord;  s.c.  a  sensor  cell;  a.a.  an  ascending  axon  or  nerve-fiber  connecting  a 
receptive  cell  from  which  it  arises  (not  shown  in  the  diagram)  with  the  sensor  cell  in 
the  gray  matter  of  the  cerebrum.  The  nerve-fibers  which  pass  outward  from  the 
spinal  cord  to  the  glands,  blood-vessels,  and  the  muscle  walls  of  the  viscera,  have  for 
the  sake  of  simplicity  been  omitted  from  the  diagram. 


CHAPTER  XX. 
THE  SPECIAL  SENSES  AND  THE  VOICE. 

In  studying  the  structure  and  functions  of  the  nerve  system,  we 
learn  that  sensory  stimuh  are  received  in  every  part  of  the  body  by 
afferent  nerves,  and  conducted  to  sensory  cells  in  the  spinal  cord; 
there,  they  either  evoke  a  muscle  response  of  reflex  character,  or 
are  transmitted  by  connecting  tracts  to  the  brain,  where  the  result 
is  sensation  of  some  sort:  as  for  example,  of  temperature — whether  of 
the  surrounding  air,  or  of  bodies  which  we  touch;  or  of  other  con- 
ditions— whether  hard  or  soft,  wet  or  dry,  rough  or  smooth,  etc.,  etc. 
These  are  common  and  definite  sensations  and  by  them  we  gain 
knowledge  of  the  world  about  us.^ 

Others  there  are,  which  are  definable  in  general  terms  only,  and 
are  not  definitely  located,  although  plainly  felt.  For  instance,  we 
are  hungry,  or  thirsty  or  tired;  after  pain  we  have  a  sense  of  relief, 
etc.,  the  route  for  stimulus  and  response  in  these  matters  is  through 
visceral  and  vaso-motor  nerves  and  their  spinal  and  cerebral  con- 
nections, and  by  them  we  gain  acquaintance  with  our  individual 
selves. 

Still  other  mechanisms  are  adapted  to  a  more  definite  class 
of  sensations,  by  which  we  learn  still  more  extensively  to  know  the 
world  in  which  we  live;  these  are  called  the  organs  of  the  special 
senses. 

The  special  senses  are:  smell,  touch,  taste,  hearing  and  sight. 
The  organs  concerned  are  the  nose,  the  skin,  the  tongue,  the  ear  and 
the  eye. 

It  is  understood  that  all  consciousness  of  sensation  is  based  upon 
the  final  reception  of  sensory  impressions  by  the  brain.  So  far  as  a 
"sense"  may  be  said  to  reside  anywhere,  it  resides  in  the  hrain,  for 
without  it  there  are  no  senses  as  we  know  them. 

^  We  do  not  now  refer  to  cranial  nerves  in  which  the  arrangement  is  similar  but 
more  intricate. 

270 


THE    SENSE    OF    SMELL.  271 

The  nose  is  the  organ  of  the  sense  of  smell.  In  the  nasal 
chambers  is  a  layer  of  special  cells — olfactory  cells — supported 
by  a  basement  membrane,  forming  the  Schneiderian  membrane  (or 
pituitary  membrane).  The  upper  part  only  of  the  nose  is  the 
olfactory  region.  Here  the  sensory  nerves  arise  which  proceed 
through  the  foramina  in  the  roof  of  the  nose  (the  cribriform  plate) 
to  the  brain. 

In  quiet  respiration  most  of  the  air  passes  in  and  out  through 
the  lower  parts  of  the  nasal  chambers,  diffusing  gradually  into  the 
upper  parts.  Although  most  odors  are  readily  perceived  as  soon 
as  one  comes  into  the  atmosphere  containing  them,  a  slight  odor 
is  better  appreciated  by  means  of  an  effort  to  draw  the  air  through 
the  olfactory  region,  in  other  words,  a  sniff.  The  odorous 
particles  are  thus  brought  into  contact  with  the  olfactory  cells, 
and  the  impressions  made  upon  them  are  transmitted  by  the  delicate 
olfactory  nerves  through  the  cribriform  plate  to  the  olfactory  bulbs 
and  thence  by  the  olfactory  tracts  to  the  olfactory  center  in  the 
temporal  lobe  of  the  brain. 

The  sense  of  smell  is  valued  for  the  pleasurable  sensations  which 
it  affords,  as  an  adjunct  to  the  sense  of  taste,  and  as  a  sentinel  to 
warn  us  of  danger  when  in  the  vicinity  of  irritating  or  poisonous 
gases,  etc.  The  degree  of  development  of  this  sense  in  lower 
animals  is  remarkable;  they  readily  "scent  danger." 

THE  SENSE  OF  TOUCH. 

The  skin  and  the  mucous  membrane  of  the  mouth  constitute 
the  organ  of  the  special  sense  of  touch  (all  mucous  membranes  are 
sensitive  to  temperature  and  pain,  but  only  that  of  the  mouth  is 
sensitive  to  touch). 

The  special  nerve  endings  are  situated  in  the  deeper  layers  and 
the  papillae  (general  description  page  214).  And  upon  their  number 
and  nearness  to  the  surface,  depends  the  acuteness  of  this  sense. 
(An  area  covered  by  thick  layers  of  epidermis  is  not  so  sensitive  as 
one  where  it  is  thin;  and  vice  versa.) 

There  are  several  forms  of  nerve  endings :  tactile  cells,  for  common 
sensations,  found  throughout  the  skin  in  the  deeper  layers  and  the 
papillae;  touch  corpuscles,  also  in  the  papillae  and  especially  numerous 
in  the  palm  and  fmger  tips,  where  sensation  is  particularly  acute; 


272  ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 

other  forms  in  muscles  and  tendons;  others  still,  for  the  perception 
of  heat  and  cold,  etc.,  etc. 

The  sense  of  touch  includes  many  varieties  of  impressions  by- 
means  of  which  we  may  judge  of  surroundings,  and  gain  the  neces- 
sary knowledge  concerning  the  external  world  whereby  we  can 
adjust  ourselves  to  its  conditions. 

Simple  contact  evokes  no  sensation  without  a  certain  degree  of 
pressure;  touch  and  pressure  are  therefore  closely  related;  with 
increased  pressure  comes  the  impression  of  weight.  If  pressure  is 
sufficiently  increased,  fain  will  be  felt,  which  is  due  to  the  disturb- 
ance of  nerves  more  deeply  situated. 

Again,  a  touch  imparts  also  a  sensation  of  place,  the  place  where 
it  occurs;  therefore  the  sense  of  touch  includes  the  place  sense. 

THE  SENSE  OF  TASTE. 

The  tongue  is  spoken  of  as  the  organ  of  taste,  since  it  bears 
the  taste  buds.  (For  general  description  of  the  tongue  see  page 
121.)  The  sense  of  taste  may  be  regarded  as  a  specialization  of 
the  sense  of  touch  and  the  two  mechanisms  somewhat  resemble 
each  other. 

The  nerve  endings  which  are  developed  for  this  purpose  are 
scattered  over  the  surface  of  the  tongue,  and  in  (certain  of)  the 
papillae,  in  the  palate  and  palatine  arches  (possibly  sometimes  in 
the  pharynx).  They  are  found  in  small  oval  bodies  called  taste 
buds,  which  are  in  direct  connection  with  the  gustatory  nerves. 

In  order  to  excite  the  nerves  of  taste,  substances  must  be  either 
already  in  solution  or  soluble  by  the  saliva;  a  perfectly  dry  substance 
may  be  felt  by  the  tongue  and  its  temperature,  etc.,  will  be  appreci- 
ated, but  it  cannot  be  tasted.  Although  all  flavors  may  be  recog- 
nized in  all  parts  of  the  tongue,  some  are  more  keenly  appreciated 
in  one  portion  than  another;  for  example:  the  bitter  flavors  are  more 
plainly  tasted  in  the  posterior  region,  while  perception  of  sweets  is 
more  marked  in  the  anterior  parts.  The  borders  seem  to  apprehend 
acids  more  quickly  than  the  dorsum. 

Touch,  temperature,  and  smell  are  all  associated  with  taste.  If 
a  substance  is  too  hot  the  sense  of  taste  is  overcome  by  the  sense  of 
pain.  Many  people  who  have  been  deprived  of  the  sense  of  smell 
(by  disease  or  injury)  assert  that  they  no  longer  possess  the  sense  of 
taste,  or  that,  if  present,  it  is  greatly  impaired. 


THE    EAR. 


273 


Fossa 


Tragus 


Lobule 


—  Fossa 


Helix 


Antihelix 


THE  SENSE  OF  HEARING. 

The  organ  of  the  sense  of  hearing  is  the  ear.  It  has  three 
di\Tsions:  external,  middle,  and  internal  (Fig.  191). 

The  external  ear  is  that  part  which  is  on  the  outside  of  the 
skull.  The  expanded  portion,  mostly  of  cartilage  covered  with  skin, 
is  the  auricle;  the  deepest  depression  is  the  concha,  and  the  opening 
at  the  bottom  of  the  concha 
leads  to  the  external  audi- 
tory canal  (or  meatus). 

This  auditory  canal  is 
one  and  one-quarter  inches 
in  length,  formed  partly 
by  the  cartilage  of  the 
auricle  and  partly  by  the 
temporal  bone.  It  curves 
slightly  upward,  and  then  Antitragus 
downward  and  forward.  It 
is  lined  with  skin  which 
bears  stiff  hairs  in  the  outer 
portion,  and  contains  the 
glands  which  secrete  "ear 
wax"  {ceruminous  glands). 
It  is  important  to  remember  the  length  and  direction  of  this  canal. 

The  membrane  at  the  end  of  the  canal  is  called  the  membrana 
tympani,  or  membrane  of  the  drum.  It  is  a  fibrous  membrane 
covered  with  very  sensitive  skin  on  the  outer  surface,  and  mucous 
membrane  within  (Fig.  192). 

The  middle  ear  is  the  tympanum,  or  drum.  It  consists  of  a  small 
cavity  in  the  petrous  bone,  on  the  inner  side  of  the  membrane  of  the 
drum.  Its  height  is  barely  half  an  inch,  and  the  other  measurements 
are  smaller  still.  It  contains  the  little  bones  and  forms  the  beginning 
of  the  auditory  tube. 

The  auditory  (or  Eustachian)  tube  begins  in  the  wall  of  the 
middle  ear  and  ends  as  a  roll  of  cartilage  opening  into  the  pharynx. 

The  tympanum  is  really  an  air  chamber,  since  it  communicates 

with  the  throat  by  the  auditory  (or  Eustachian)  tube,  and  both  tube 

and  tympanum  are  lined  with  a  continuation  of  the  same  mucous 

membrane.     An  ojjcning  at  the  back  of  the  tympanum  leads  into 

18 


Fig. 


191. 


-The  External  Ear  (Morris). 


274 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


the  mastoid  antrum,  and  through  this,  inflammation  of  the  middle 
ear  frequently  extends  to  the  mastoid  cavities. 

Note. — The  mucous  membrane  of  the  pharynx  is  continued 
through  the  auditory  tube  into  the  tympanum,  and  through  that  into 
the  mastoid  cells. 

Two  openings  lead  from  the  tympanum  to  the  internal  ear — 
the  oval  (or  vestibular)  window  and  the  round  (or  cochlear)  window. 

The  round  window  is  closed  by  a  membrane  called  the  secondary  membrane 
of  the  tympanum.  The  oval  window  is  closed  by  a  fibrous  layer  and  the  base 
of  the  stirrup  bone  (p.  275). 


Semicircular      Wax 
canals  glands 


Drum  membrane 


Cochlea 
Cavity  of  tym 
panum     or 
drum 


Parotid  gland 


Styloid  process 

Internal 
carotid    artery 


Auditory  tube 


Fig.  192. — The  Ear  (Morris). 


The  internal  ear  is  still  more  deeply  situated  in  the  petrous 
bone.  It  is  extremely  complicated,  consisting  of  semicircular  canals, 
vestibule,  and  cochlea,  and  well  named  the  labyrinth.  There  are 
three  semicircular  canals  placed  at  right  angles  to  each  other;  the 
cochlea  resembles  a  snail-shell  in  form,  and  both  communicate  with 
the  vestibule  which  is  between  them. 


AUDITORY    NERVE.  275 

The  cochlea  communicates  with  the  tympanum  by  the  round  or  cochlear 
window,  and  the  vestibule  communicates  with  the  tympanum  by  the  oval  or 
vestibular  window. 

The  internal  ear  or  labyrinth,  contains  a  clear  fluid  called  perilymph.  Lying 
in  the  perilymph  is  a  membranous  labyrinth  containing  endolymph.  The  mem- 
branous labyrinth  is  of  the  same  shape,  having  all  the  different  parts  as  the  bony 
labyrinth. 

Ossicles. — A  chain  of  three  ossicles  (or  httle  bones)  is  suspended 
across  the  tympanum — the  malleus, 
incus,  and  stapes.  The  malleus  (or 
hammer)  is  attached  by  the  handle 
to  the  membrane  of  the  drum,  the 
incus  (or  anvil)  comes  next,  and 
then  the  stapes  (or  stirrup)  with  its 
base  fitting  the  oval  window  of  the 
middle  ear.  Any  vibration  of  the 
membrane  of  the  tympanum  is  at  Fig.  193. — Bones  of  the  Ear 
once  transmitted  by  this  chain  of 

bones  across  the  tympanum,  and  through  the  oval  window  to  the 
nerves  of  the  internal  ear  (Fig.  193). 

Nerves  of  the  Internal  Ear. 

The  cochlear  division  of  the  auditory  nerve  is  the  true  nerve 
of  hearing.  Its  terminal  filaments  are  within  the  cochlea;  they 
receive  impressions  transmitted  by  the  vibrating  chain  of  bones  in 
the  tympanum,  through  the  oval  window,  and  conduct  them  to  the 
brain.  The  vestibular  division  of  the  auditory  nerve  is  distributed 
in  the  vestibule  and  semicircular  canals;  it  is  not  concerned  in  hearing, 
but  is  necessary  to  the  power  of  preserving  equilibrium  in  standing, 
walking,  etc.  A  person  in  whom  this  nerve  has  been  destroyed 
cannot  walk  steadily,  and  is  not  subject  to  sea-sickness. 

Summary. — The  function  of  the  external  ear  is  to  gather  and 
direct  the  sound  waves  to  the  membrane  of  the  tympanum.  In  the 
middle  ear  (or  tympanum)  the  vibrations  of  the  membrane  are  trans- 
mitted by  the  chain  of  ossicles  to  the  oval  window,  and  through  the 
perilymph  of  the  internal  ear  to  auditory  nerves  within  the  cochlea. 
The  impressions  thus  made  arc  conducted  to  the  brain  and  we  hear. 

The  vestibular  branch  of  the  auditory  nerve  is  not  stimulated  in  this  manner, 
but  by  certain  changes  in  the  i)osition  of  the  body,  .sometimes  of  the  head  alone. 


276 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


THE  SENSE  OF  SIGHT. 

The  eye  is  the  organ  of  sight.  It  is  situated  in  the  orbital  fossa. 
It  is  a  sphere  or  globe  having  for  its  surface  three  layers  called  the 
coats  or  tunics  of  the  eye — namely  the  sclera  and  cornea  (fibrous) ,  the 
choroid  and  iris  (vascular) ,  and  the  retina  (nervous) .  They  contain 
three  transparent  structures — the  aqueous  humor,  crystalline  lens 
and  vitreous  body. 

The  sclera  is  the  "white  of  the  eye."  It  is  dense  and  tough, 
protecting  the  more  delicate  structures  within.  One-sixth  of  the 
surface  of  the  ball  in  front  is  occupied  by  the  cornea  instead  of  the 


Retina 


Choroid 


Sclera 


m~  Cornea 

Iris 

Ciliary  processes 

Lymph  canal 

Ciliary  muscle 


Fig.  194. — A  Section  of  the  Eye  (Holden). 
I,  Anterior  chamber;  2,  posterior  chamber.     The  aqueous  humor  occupies  the  two 

chambers. 


sclera,  and  this  also  is  dense  and  tough,  but  transparent  for  the 
admission  of  light.  It  contains  no  blood-vessels,  but  many  tiny 
lymph-spaces.  It  is  the  most  prominent  part  of  the  eyeball,  and 
its  convexity  may  be  seen  by  looking  across  an  eye  from  the  side. 
The  junction  of  the  cornea  with  the  sclera  resembles  the  fitting  of  a 
watch-crystal  in  its  case. 

The  portion  of  the  sclera  which  is  visible  when  the  eyelids  are 
separated,  and  also  the  cornea,  are  both  covered  by  a  thin  membrane 
called  the  conjunctiva;  it  is  a  modified  mucous  membrane,  bearing 
blood-vessels  which  can  be  easily  seen,  especially  if  a  little  dilated. 

The  choroid. — The  middle  coat,  next  to  the  sclerotic,  is  neither 
dense  nor  tough,  but  is  made  up  of  fine  tissue  fibers  bearing  a  very 


THE    EYE.  277 

delicate  and  close  network  of  blood-vessels.  It  is  the  vascular  coal  of 
the  eye,  and  lines  the  sclera  only,  not  the  cornea.  Many  pigment 
cells  are  contained  in  the  choroid  coat,  gi\'ing  to  it  a  deep  brown 
color  so  that  it  makes  a  dark  chamber  of  the  eye  (Fig.  195). 

The  iris. — There  is  no  choroid  behind  the  cornea.  Its  place 
is  supplied  by  the  iris,  which  resembles  a  circular  curtain  attached 
by  its  edge  to  the  choroid,  and  ha\-ing  a  round  aperture  in  the  center 
called  the  piipil  or  the  "  star  of  the  eye."    The  iris  contains  a  network 


Fig.  195.— The  Choroid  axd  Iris  (Holden;. 

of  fine  vessels  and  pigment  cells,  varying  in  color  according  to  the 
amount  of  pigment.  (Blue  eyes  have  least,  black  eyes  most.)  It 
has  muscular  fibers  arranged  in  two  sets — circular,  or  ring  fibers,  and 
so-called  radiating,  or  straight  fibers.  The  circular  fibers  surround 
the  pupil.  Thus,  when  they  contract,  as  in  a  bright  light,  they 
diminish  its  size.  The  straight  fibers  run  from  the  outer  border  of 
the  iris  toward  the  pupil,  and  therefore  when  they  contract  they  act 
upon  the  margin  to  enlarge  the  opening.  Briefly,  the  pupil  is 
contracted  by  the  circular  fibers,  and  dilated  by  the  straight  or  radiat- 
ing fibers,  thus  regulating  the  amount  of  light  admitted  within  the  eye. 

The  retina  is  the  innermost  coat,  of  many  layers,  wdthin  the  cho- 
roid. This  is  a  very  delicate  structure  in  which  are  the  beginnings 
of  the  optic  nerve  fibers.  It  is  the  coat  which  is  essential  to  vision — 
no  retina,  no  vision.  The  outermost  layer  of  the  retina  is  the  one 
which  contains  the  rods  and  cones,  or  the  visual  cells.  Like  the 
sclera  and  choroid,  the  retina  is  incomplete  in  front. 

From  the  cells  in  the  retina  delicate  fibers  are  prolonged  and 
gathered  together  to  make  the  optic  nerve,  which  pierces  the  choroid 


278  ANATOMY  AND   PHYSIOLOGY  FOR   NURSES. 

and  the  sclerotic,  passes  through  the  optic  foramen  of  the  orbit,  and 
thence  back  to  the  brain.  The  optic  disc  is  the  spot  where  the  optic 
nerve  leaves  the  retina;  it  is  situated  a  little  to  the  nasal  side  of  the 
center  of  the  retina  (Fig.  196), 

The  macula  lutea  is  a  spot  in  the  center  of  the  retina  opposite  the  mid-point 
of  the  normal  pupil.  In  the  center  of  this  spot  is  a  depression  called  the  fovea 
centralis  which  is  the  center  of  vision;  only  the  c©ne-shaped  visual  cells  are  here 
present. 


Macula  '    L  I  W        ^-,    -ZIXl^^ Retinal  vessels 


Fig.  196. — The  Retina  as  seen  w^ith  the  aid  of  the  Ophthalmoscope  (Morris). 

The  vitreous  body  is  glass-like,  as  its  name  signifies,  both  in 
appearance  and  transparency.  It  consists  of  a  jelly-like  substance 
contained  in  a  hyaloid  membrane  within  the  three  coats.  It  trans- 
mits and  directs  the  rays  of  light  to  the  retina;  also  it  aids  in  pre- 
serving the  shape  of  the  eyeball  (Fig.  194). 

The  crystalline  lens  is  situated  immediately  in  front  of  the 
vitreous  body,  in  a  shallow  depression  like  a  cup  on  the  anterior 
surface,  and  held  there  by  delicate  fibers  which  act  as  a  suspensory 
ligament.  It  is  a  double  convex  lens  with  a  capsule,  both  perfectly 
transparent  so  that  light  may  pass  through,  and  it  is  able  to  converge 
the  rays  of  light  so  that  they  will  fall  correctly  upon  the  retina.  The 
lens  is  behind  the  iris,  the  margin  of  the  pupil  resting  lightly  upon  it. 

The  ciliary  muscle  is  in  the  interior  of  the  eyeball,  around  the  junction  of  the 
choroid  and  iris,  thus  lying  a  little  farther  forvi^ard  than  the  border  of  the 
lens.  Its  action  modifies  the  shape  of  the  lens,  by  which  arrangement  the  eye  is 
able  to  accommodate  itself  to  the  different  distances  of  surrounding  objects. 
This  is  the  process  of  accommodation.  To  "paralyze  the  accommodation"  is  to 
make  the  ciliary  muscle  powerless,  so  that  the  eye  cannot  try  to  see  near  objects, 
as  it  always  does  unconsciously,  in  its  normal  condition.     Atropin  will  do  this. 

Clinical  notes. — Inflammation  of  the  iris,  or  iritis,  may  cause  adhesions  to 
the  lens  unless  the  margin  of  the  pupil  be  drawn  away.     This  is  the  reason  for 


APPENDAGES    OF    THE    EYE. 


279 


the  use  of  atropin,  which  weakens  the  circular  fibers  while  it  stimulates  the 
straight  ones,  or,  in  other  words,  dilates  the  pupil. 

Cataract  is  a  thickening  of  the  lens  which  makes  it  opaque  and  gives  it  a 
milky  appearance.  The  remedy  is  excision  or  removal  of  the  lens,  after  which 
a  convex  lens  of  glass  in  front  of  the  eye  gives  a  good  degree  of  vision.  A 
cataract  is  in  an  eye,  not  over  it,  and  must  be  taken  out,  not  off. 

Aqueous  humor  and  chambers  of  the  eye. — The  space  be- 
tween the  cornea  and  the  lens  is  partially  divided  by  the  iris  into  two 
portions — the  anterior  and  posterior  chambers  of  the  eye.  They  con- 
tain a  thin  clear  fluid,  called  the  aqueous  humor,  which  floats  the 
iris  and  aids  in  preserving  the  shape  of  the  cornea  (Fig.  194). 

Note. — The  rays  of  light  which  fall  upon  the  retina  must  first 
pass  through  the  media  (or  structures  which  direct  their  course)  in 
the  following  order:  the  cornea,  aqueous  humor,  crystalline  lens,  and 
vitreous  body.  Should  any  one  of  these  lose  its  transparency,  vision 
would  be  impaired  or  perhaps  lost. 

The  capside  of  Tenon  is  a  fibrous'capsule  outside  the  eyeball,  loosely  investing 
it  and  its  muscles.  It  is  disposed  like  a  serous  membrane — having  two  layers, 
one  of  which  lines  the  orbit  and  the  other  is  loosely  applied  to  the  eyeball. 

Appendages  of  the  Eye. 

The  eyebrows,  resting  upon  the  superciliary  ridges,  or  ele- 
vations caused  by  the  frontal  sinuses  (p.  17). 


Superior  lacrimal    gland 
Inferior  lacrimal  gland  - — 


Ducts  from  superior 
gland 


Upper  eyelid  partly 
divested  of  skin 


Upper  punctum 

Lacrimal  sac,  near  its 
fundus 

Common  duct,  formed 
,^^  by  junction  of  upper 
t"    and  lower  ducts 

Lower  punctum 
Naso-lacrimal  duct 


Fig.  197. — Lacrimal  Apparatus  (Morris). 

The  eyelids  (or  palpebral) ,  attached  to  the  margin  of  the  orbits 
and  necessary  for  the  protection  of  the  eye.  They  have  five  layers, 
■ — skin,  smooth  and  thin;  fascia — thin  and  delicate;  muscle — the 
palpebral  portion  of  the  orbicular  muscle;  fibrous — containing  a  stiff 


28o 


ANATOMY   AND    PHYSIOLOGY    FOR    NURSES. 


plate  of  connective  tissue,  the  tarsal  plate;  and  mucous — the  layer 
which  lines  the  lid  (Conjunctiva). 

The  tarsal  glands  are  in  the  tarsal  plates;  their  oily  secretion 
prevents  the  lids  from  adhering  to  each  other.  (They  are  called 
Meibomian  glands.) 

The  angles  formed  by  the  extremities  of  the  eyelids  are  the 
medial  and  the  lateral  angles  (inner  and  outer  canthi).  At  the 
medial  angle,  each  lid  presents  a  small  elevation,  the  lacrimal  papilla, 
with  a  minute  opening  {punctum)  where  the  tears  enter  a  small  canal 
which  leads  to  the  lacrimal  sac;  from  the  lacrimal  sac  they  flow 
through  the  nasal  duct  to  the  nasal  cavity. 

The  eyelashes,  or  cilia,  are  kept  soft  and  flexible  by  an  oily 
substance  secreted  by  their  own  oil  glands  in  the  margin  of  the  lid. 


Fig.  198. — The  Muscles  of  the  Eyeball  (Holden). 
A  small  section  of  the  upper  eyelid  is  shown. 


Lacrimal  gland. — The  gland  which  secretes  the  tears.  It  is 
situated  in  the  lacrimal  fossa  of  the  frontal  bone,  beneath  the  lateral 
end  of  the  orbital  arch,  and  has  several  ducts  for  the  discharge  of 
the  tears  under  the  upper  eyelid. 

Conjunctiva. — This  is  the  sensitive  mucous  membrane  which 
is  attached  to  the  margins  of  the  eyelids  to  line  the  lids  and  cover 
the  eye.  The  tears  flow  across  it  and  keep  it  bathed,  preventing 
the  injurious  effect  of  dust  and  other  foreign  substances.  They 
are  then  conducted  by  the  little  lacrimal  canals  and  nasal  duct  to  the 


nose. 


THE    VOICE.  281 

Clinical  Note. — The  conjunctiva  is  supplied  with  blood-vessels 
most  of  which  are  invisible  except  when  they  become  congested. 
In  active  inflammation  or  conjunctivitis  they  are  so  enlarged  as  to 
give  the  membrane  a  bright  red  color. 

The  lids  are  closed  by  the  action  of  the  orbicularis  (the  palpebral 
fibers)  (p.  84).  They  are  opened  by  the  levator  palpehroe, 
which  lifts  the  upper  lid,  uncovering  the  eye,  while  the  orbicularis 
relaxes. 

Motions  of  the  eyeball. — The  eyeball  is  moved  by  six  slender 
muscles  which  have  their  origin  at  the  apex  of  the  orbit,  and  their 
insertion  upon  the  sclera  at  a  little  distance  from  the  cornea. 

The  superior  rectus  rolls  the  ball  upward. 

The  inferior  rectus  rolls  the  ball  downward. 

The  internal  rectus  rolls  the  ball  inward. 

The  external  rectus  rolls  the  ball  outward. 

The  superior  oblique  rolls  the  ball  downward  and  outward. 

The  inferior  oblique  rolls  the  ball  upward  and  outward. 

Clinical  note. — If  these  muscles  are  well  balanced  the  pupil  is  directed 
straight  forward  while  they  are  at  rest,  but  if  they  are  of  quite  unequal  strength 
the  eye  will  be  turned  habitually  in  some  special  direction.  This  condition  is 
called  squint  or  strabismus,  or  "cross-eye."  It  oftenest  happens  with  either  the 
internal  or  external  rectus. 

THE  VOICE. 

The  voice,  by  which  we  establish  most  frequent  communication 
with  the  outside  world,  is  a  special  endowment  for  the  expression  of 
ideas  awakened  by  consciousness  of  the  senses.  It  is  therefore  not 
inappropriately  considered  in  this  connection. 

The  larynx  is  the  organ  of  the  voice.  (The  larynx,  lips, 
tongue  and  teeth  are  the  organs  of  speech.)  A  brief  description  of 
the  larynx  is  given  on  page  204. 

The  structures  which  are  specially  concerned  in  the  production 
of  the  voice,  in  addition  to  the  cartilages  there  described,  are  the 
vocal  bands  (also  known  as  vocal  cords,  and  true  vocal  cords). 
These  are  stretched  across  the  larynx  from  front  to  back,  being 
attached  to  the  thyroid  cartilage  anteriorly  and  the  cricoid  poster- 
iorly, and  dividing  the  cavity  into  upper  and  lower  portions  (Fig. 
148). 


252  ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 

They  are  composed  of  fibrous  and  muscle  tissue  covered  with 
mucous  membrane.     The  space  between  them  is  the  glottis. 

Small  muscles,  belonging  altogether  to  the  larynx,  control  the 
position  and  tension  of  the  vocal  hands  by  their  action  on  the  carti- 
lages to  which  the  bands  are  attached,  thus  producing  the  differ- 
ent tones  of  the  voice  as  the  breath  passes  between  them.  Tense 
bands  and  a  narrow  glottis  are  necessary  for  a  high  note.  Lax  bands 
and  a  wide  glottis  are  the  conditions  for  a  low  note. 

Above  them  are  two  membranous  folds,  one  on  either  side, 
formerly  called /a^^e  vocal  cords. 

Note. — It  has  been  generally  taught  that  the  voice  is  caused  by  vibrations  of 
the  vocal  bands,  but  accurate  observations  by  Miss  Alice  Groff,  of  Philadelphia, 
and  other  investigators,  have  proved  that  this  is  not  the  case,  the  voice-sounds 
being  like  those  of  a  horn  rather  than  a  stringed  instrument. 

With  the  aid  of  lips,  tongue,  and  teeth,  the  voice  sounds  are  so 
modified  that  speech  becomes  possible,  and  with  it  the  expression 
of  ideas,   and   communication  between  individuals. 


CHAPTER  XXI. 
THE  PELVIC  ORGANS. 

In  the  Male  Pelvis.  In  The  Female  Pelvts. 

The  rectum.  The  rectum. 

The  urinary  bladder.  The  urinary  bladder. 

The  prostate  gland.  The  uterus. 

The  ovaries,  and  uterine  tubes. 
The  vagina. 

The  Rectum  is  already  described  (page  136). 

The  Bladder  is  the  receptacle  and  reservoir  for  the  urine  and  is 
situated,  in  the  pelvis  just  behind  the  pubic  bones.  It  is  a  7ion- 
striated  muscular  sac,  lined  v^ith  mucous  membrane  which  lies  in 
irregular  folds  when  the  sac  is  empty,  but  becomes  smooth  when 
it  is  filled.  It  has  an  incomplete  serous  covering  above  and 
posteriorly. 

The  upper  portion  of  the  bladder  is  the  vertex;  the  lower  part  is 
the  base.  There  are  three  openings  in  the  bladder  wall,  two  for  the 
entrance  of  urine  and  one  for  expelling  it. 

The  urine  enters  through  the  two  ureters  (p.  213)  or  ducts  of  the 
kidney,  which,  having  reached  the  pelvis,  proceed  below  the  broad 
ligaments,  to  run  forward  and  enter  the  base  of  the  bladder,  there 
discharging  the  urine. 

The  opening  for  the  escape  of  the  urine  is  called  the  internal 
orifice.  It  leads  into  a  canal  called  the  urethra  which  ends  at  the 
external  orifice  (or  meatus) ,  and  through  it  the  urine  is  expelled  from 
the  body.  The  internal  orifice  is  guarded  by  circular  muscle  fibers 
forming  a  sphincter — the  sphincter  ve sic ce  (sphincter  of  the  bladder). 
The  openings  of  the  ureters  are  about  one  inch  from  the  internal 
orifice,  and  the  same  distance  apart,  thus  these  three  openings 
mark  the  corners  of  a  triangle  at  the  base  of  the  bladder,  called 
the  trigone. 

The  urethra  is  a  fibro-muscular  canal  lined  with  mucous  mem- 
brane.    It  begins  at  the  internal  orifice  of  the  bladder,  ends  at  the 

283 


284 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


external  orifice  or  meatus  urinarius,  and  conducts  the  urine  from  the 
body. 

The  female  urethra  is  about  one  and  one-half  inches  long  and 
I  /4  inch  wide,  but  is  very  distensible.  It  curves  slightly  downward 
toward  the  external  meatus. 

Clinical  note. — The  catheter  should  pass  a  little  upward  after  entering  the 
urethra  (Fig.  199). 

A  urethral  caruncle  is  an  exceedingly  painful  little  tumor  pro- 
jecting from  the  urethral  mucous  membrane.  It  is  a  collection  of 
sensitive  blood-vessels  and  nerves. 


Bladder        Uterus 


Urethra 


Anus  (rectum  distended) 


Fig.  ic 


-Pelvic  Organs,  Female  Pelvis  (Holden), 
Dotted  lines  indicate  peritoneum. 


The  prostate  gland  is  situated  at  the  base  of  the  male  Uadder, 
immediately  in  front  of  the  rectum  and  surrounding  the  first  portion 
of  the  urethra. 


Clinical  Note. — When  empty,  the  bladder  lies  entirely  in  the  pelvis,  but  if  it 
contains  more  than  eight  ounces  it  begins  to  rise  into  the  abdomen.  It  has  been 
known  to  extend  as  high  as  the  umbilicus. 

Surgical  note. — The  peritoneum  covers  the  vertex  and  a  portion  of  the 
posterior  surface  only;  therefore,  the  bladder  may  be  entered  in  front  through  an 
incision  just  above  the  symphysis  pubis  without  wounding  the  peritoneum. 


THE   PELVIC    ORGANS.  285 

THE  UTERUS  AND  APPENDAGES. 

These  constitute  the  internal  generative  organs. 
The  appendages  are  the  uterine   (or  Fallopian)  tubes  and  the 
ovaries  (Fig.  200). 

The  Uterus. 

The  uterus,  or  womb,  is  situated  between  the  bladder  and  the 
upper  part  of  the  rectum.     It  is  a  hollow  organ  shaped  somewhat 

POSTERIOR  SURFACE  OF  BODY  OF  UTERUS 

TTtero-ovarian  ligament 
OVARY 

FALLOPIAN  TUBE 

Broad  ligamenfc 


Infundibulum 
Fimbria 
Broad  1  gament 


\aginal  walls 


Fig.  200. —  LihKub  amj  .vi'i'i-ADAGtb,  POSTERIOR  (Morris). 

like  a  pear,  about  two  and  one-half  or  three  inches  long,  and  one  and 
one-half  inches  wide  at  the  larger  end,  which  is  called  the  fundus 
and  is  placed  uppermost. 

The  uterus  is  composed  of  non-striated  muscles  arranged  in 
three  layers,  and  lined  with  mucous  membrane  bearing  ciliated  epi- 
thelium. Its  walls  are  about  three-eighths  of  an  inch  thick.  It 
consists  of  two  portions,  the  body  and  the  neck  or  cervix,  the  body 
being  a  little  longer  of  the  two. 


286 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


The  body  is  flattened,  but  is  more  convex  at  the  back  than  in 
front,  while  the  cervix  is  round. 

The  cavity  of  the  uterus  corresponds  to  the  general  shape  of  the 
organ,  being  triangular  in  the  body  and  round  in  the  cervix.  At  the 
upper  angles  of  the  body  are  the  openings  which  lead  into  the  Fal- 
lopian tubes.     Between  the  body  and  the  cervix  is  the  internal  os, 

the  opening  at  the  lower 
extremity  of  the  cervix 
being  called  the  external 
OS,  which  is  bordered  by 
the  anterior  and  posterior 
lips.  The  uterus  is  cov- 
ered with  peritoneum,  ex- 
cept in  front  of  the  cervix. 
When  the  uterus  re- 
cieves  an  impregnated 
ovum  its  function  is  ex- 
ercised in  protecting  and 
nourishing  the  growing 
embryo  until  it  becomes 
a  fully  developed  fetus. 
The  mucous  membrane 
thickens  to  form  a  bed  for  the  embryo,  and  becomes  a  part  of  the 
placenta  or  "afterbirth."  The  muscle  fibers  grow  in  size  and 
number  and  the  weight  increases  from  the  original  ounce  and  a 
half  to  one  or  more  pounds. 

The  function  of  the  uterus  is  concluded  with  the  expulsion  of  the 
fetus  and  placenta.  It  then  contracts  rapidly,  and  the  process  of 
involution  softens  and  discharges  the  remains  of  tissue  which  it  no 
longer  needed. 

Clinical  note. — Subinvolution  is  incomplete  involution. 

Position. — The  fundus  of  the  uterus  is  normally  inclined  somewhat  forward,, 
while  the  oo  externum  looks  downward  and  backward.  If  the  fundus  turns  toa 
ar  forward  this  is  anteversion;  if  it  inclines  backward,  retroversion. 

A  bend  may  exist  where  the  neck  joins  the  body.  This  is  Jlexion.  When 
the  body  is  bent  forward,  this  is  anteflexion;  when  backward,  retroflexion. 

The  Uterine  Tubes  (Fallopian  Tubes). 
The  uterine  tubes  (Fallopian  tubes)  two  in  number  (Fig.  200), 
extend  outward  from  the  upper  angles  of  the  uterus;  they  have  a 


Fig.  201. — The  Uterus. 
Showing  cavity  and  attachment  of  vagina  (Morris) 


THE    OVARIES. 


287 


fibro-muscular  structure  and  are  lined  with  mucous  membrane. 
Each  tube  is  about  four  inches  long.  At  the  beginning  it  is  only  large 
enough  to  allow  the  passage  of  a  small  bristle,  but  it  becomes  larger 
toward  the  end,  expanding  into  a  trumpet-shaped  extremity  called 
the  infundibulum,  which  is  fringed  or  fimbriated,  and  which  is  con- 
nected with  the  ovary  below  by  a  slender  band  {or  fimbria). 

The  function  of  the  uterine  (or  Fallopian)  tube  is  to  convey  the 
ovum  from  the  ovary  to  the  cavity  of  the  uterus. 


The  Ovaries. 

The  ovaries,  two  in  number,  lie  on  either  side  of  the  body  of 
the  uterus,  each  one  being  connected  to  it  by  a  short  cord  called  the 
ovarian  ligament.  An  ovary  is  about  three-quarters  of  an  inch  long, 
a  half-inch  wide,  and  shaped  like  an  almond  (Figs.  200,  202). 

The  ovaries  ore  covered  with 
peritoneum  (except  at  the  border 
where  vessels  enter  and  leave). 

Structure  of  the  ovary. — 
A  collection  of  connective-tissue 
fibers  enclosing  many  vessels 
and  nerves,  and  a  multitude  of 
little  ovisacs  (egg  sacs)  called 
Graafian  follicles.  These  fol- 
licles are  at  first  microscopic  in 
size,  but  when  developed  they 
may  be  seen  by  the  naked  eye.     Each  one  contains  an  ovuniy  or  egg. 

Ovulation. — As  the  follicle  with  its  ovum  grows  in  size  it  ap- 
proaches the  surface  of  the  ovary,  and  when  it  is  mature  the  sac 
ruptures  and  the  ovum  escapes,  to  be  taken  by  the  uterine  (or  Fal- 
lopian) tube  to  the  uterus,  from  which  it  is  discharged  through  the 
vagina,  usually  with  a  quantity  of  blood. 

The  function  of  the  ovary  {ovulation)  begins  with  puberty,  which 
is  the  maturing  of  the  pelvic  organs  and  mammary  glands.  It  is 
usually  established  at  about  fourteen  years  of  age  (earlier  in  warm 
climates,  later  in  cold).  From  that  time  the  development  of  at  least 
one  ovum  occurs  in  about  every  twenty-eight  days. 

Menstruation  is  the  periodical  discharge  of  blood  from  the 
uterus.     The  mucous  membrane  thickens  and  sheds  its  superficial 


Fig.  202. — Ovary  with  Mature 
Graafian  Follicle  about  ready  to 
Burst  (Ribomont-Dessaignes-Lewis) . 


255  ANATOMY   AND    PHYSIOLOGY    FOR   NURSES. 

cells,  which  are  renewed  after  the  flow  ceases.  This  probably  accom- 
panies ovulation.  When  an  impregnated  ovum  reaches  the  uterus 
menstruation  is  suspended. 

The  cessation  of  menstruation  is  the  menopause  or  climacteric. 
It  occurs  at  about  forty-five  years  of  age  (and  may  be  as  late  as 
fifty  or  over).  It  is  followed  by  gradual  atrophy  of  the  generative 
organs. 

Corpus  luteum  is  the  name  given  to  a  yellow  substance  which  forms  in  the 
ruptured  Graafian  follicle.  It  ordinarily  shrinks  and  disappears  within  a  month. 
The  corpus  luteum  left  by  an  impregnated  ovum,  however,  grows  larger  and 
remains  present  until  the  end  of  pregnancy. 

The  Vagina. 

The  Vagina  is  the  muscular  canal  extending  from  the  uterus  to 
the  surface  of  the  body,  where  it  terminates  at  the  vaginal  orifice 
(Figs.  199,  200). 

It  is  situated  between  the  base  of  the  bladder  in  front  and  the 
lower  portion  of  the  rectum  behind,  from  which  organs  it  is  separated 
by  connective  tissue  septa  {vesico-vaginal,  and  recto-vaginal  septa). 
It  curves  slightly  forward,  and  is  four  inches  long  in  its  posterior 
wall  and  about  two  and  three-quarter  inches  in  the  anterior.  It  has 
two  layers  of  muscles,  strengthened  by  fibrous  tissue  and  lined  by 
mucous  membrane  which  lies  in  transverse  folds.  The  columns  of 
the  vagina  are  two  median  ridges,  one  on  the  anterior  and  one  on  the 
posterior  wall,  extending  throughout  their  length. 

The  vagina  is  attached  to  the  cervix  of  the  uterus  at  a  little 
distance  above  the  external  os  (about  half  an  inch  in  front  and  three- 
quarters  of  an  inch  at  the  back) ;  therefore  the  examining  finger  may 
feel  the  cervix  projecting  into  the  canal.  This  is  the  infra-vaginal 
portion  of  the  cervix  (Fig.  199,  200). 

Note. — The  urethra  lies  close  to  the  anterior  vaginal  wall,  feeling 
like  a  thick  cord  in  the  septum  between  the  two  canals  (the  urethro- 
vaginal septum). 

Ligaments  of  the  Uterus. 

The  uterus  is  sustained  in  the  pelvis  by  folds  of  peritoneum  which 
connect  it  to  the  pelvic  walls  and  to  the  bladder  and  rectum.  The 
principal  ones  are  the  broad  ligaments. 


THE  EXTERNAL  GENERATIVE  ORGANS.  289 

The  hroad  ligaments  are  folds  of  peritoneum  extending  laterally 
from  the  sides  of  the  uterus,  like  wings,  to  the  sides  of  the  pelvic 
cavity.  Each  fold  encloses  the  uterine  tube,  ovary,  and  round  liga- 
ment of  its  own  side. 

The  round  ligaments  are  two  muscular  and  fibrous  cords,  which 
extend  from  the  angle  of  the  uterus  lateral- ward  and  forward  through 
the  inguinal  canal,  to  be  attached  to  the  tissues  upon  the  pubic  bone. 
They  aid  in  preserving  the  normal  position  of  the  uterus  with  the 
fundus  forward. 

The  External  Generative  Organs. 

The  pudendum  muliebre  {vulva). — The  name  given  to  the 
parts  situated  in  front  of  the  pubic  arch  of  the  female  pelvis.  They 
are: 

The  mens  veneris,  a  cushion  of  adipose  and  fibrous  tissue  in 
front  of  the  body  of  the  pubic  bone. 

The  labia  maj  era. — Two  folds  of  skin  containing  adipose  and 
loose  connective  tissue,  continuous  in  front  with  the  mons,  and 
joined  together  posteriorly  by  a  fold  of  skin  called  the  posterior 
commissure,  about  an  inch  in  front  of  the  anus.  (The  depression  in 
front  of  this  commissure  is  \h.Q  fossa  navicularis.) 

The  space  between  the  labia  majora  is  the  pudendal  cleft. 

The  labia  minora. — Two  folds  situated  between  the  labia 
majora,  about  one-half  as  long,  and  joined  anteriorly  in  the  hood  of 
the  clitoris.  Between  them  is  the  space  called  the  vestibule.  (They 
sometimes  unite  posteriorly  in  a  thin  fold  called  the  frenulum.) 

The  clitoris. — A  small  body,  somewhat  less  than  an  inch  in 
length,  nearly  covered  by  the  hood.  It  contains  many  vessels  and 
nerves.  The  extremity  is  called  the  glatts  of  the  clitoris;  the  hood 
is  normally  free  from  the  glans  and  if  adhesions  form  they  should  be 
separated,  since  they  are  a  source  of  nervous  irritation. 

The  vestibule. — A  triangular  space  below  the  clitoris,  and 
between  the  labia  minora.  In  the  middle  of  the  vestibute  is  the 
orifice  of  the  urethra,  or  external  meatus. 

Below  the  vestibule  is  the  orifice  of  the  vagina,  or  vaginal  orifice, 
partially  closed  by  a  circular  fold  of  mucous  membrane  called  the 
hymen. 

19 


290 


ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 


The  ragged  edges  left  by  rupture  of  the  hymen  are  called  carunculcs  myrti- 
formes.  An  imperforate  hymen  is  one  which  extends  entirely  across  the  vaginal 
orifice,  closing  it  altogether.  A  little  way,  laterally,  from  the  middle  of  the 
hymen  are  the  openings  of  the  ducts  of  the  glands  of  Bartholin,  one  on  either  side. 

The  peritonetim  of  the  pelvis  (Fig.  199)  is  a  portion  of  the  general  perito- 
neum. It  lines  the  pelvic  walls,  covers  the  rectum  (except  the  lowest  part)  and 
other  pelvic  organs,  and  the  floor. 

In  the  male  pelvis  it  dips  between  the  rectum  and  bladder  forming  the 
recto-vesical  pouch. 

In  the  female  pelvis  it  forms  a  utero-vesical  pouch  in  front  of  the  uterus,  and 
a  utero-rectal  pouch  behind  it.     It  also  extends  over  the  tubes,  ovaries,  and  round 

ligaments  at  the  sides,  thus  making 


the  folds  called  the  broad  ligaments, 
which  connect  the  uterus  with  the 
sides  of  the  pelvic  cavity. 

The  utero-rectal  pouch  is  the 
pouch  of  Douglas  (or  Douglas's  cul- 
de-sac).  It  is  the  lowest  part  of  the 
peritoneal  cavity,  extending  down 
an  inch  or  more  behind  the  vagina. 

Note. — The  pelvis  of  the  infant^ 
is  undeveloped  and  the  pelvic 
organs  lie  partly  in  the  abdomen. 
As  growth  advances  they  are  finally 
contained  in  the  pelvis,  at  about 
the  fourteenth  year. 


Perineum . — The     name 

Fig.  203. — Showing  Testis  and  Ductus  .  ,         .      .  _ 

Deferens  Suspended  by  Spermatic  Cord      perineum     properly    Signifies 

(^°^^^")-  the  parts  bounded  by  the  out- 

let of  the  pelvis,  but  we  generally  apply  it  to  the  portion  in  front  of 
the  rectum. 

In  the  female  perineum,  the  part  between  the  lower  ends  of  the 
vagina  and  rectum  is  the  perineal  body.  This  is  a  triangular  body 
composed  of  connective  tissue  and  adipose,  the  base  of  the  triangle 
being  covered  by  skin  and  measuring  about  one  inch,  between 
the  vulva  and  the  anus.  It  contains  several  muscles,  some  of  which 
are  connected  with  the  sphincter  ani. 

The  perineum  is  distensible,  and  stretches  to  a  remarkable  extent 
during  labor. 

From  the  male  perineum  a  pouch  of  skin  and  fascia  is  suspended, 
called  the  scrotum.  The  fascia  contains  scattered  muscle  fibers  and 
is  called  the  dartos. 


THE    TESTES    AND    SPERMATIC    CORD.  29I 

The  scrotum  contains  the  testes  which  are  two  in  number,  the 
right  and  the  left.  They  consist  essentially  of  minute  tubes  in  which 
the  seminal  fluid  is  secreted,  and  which  open  into  larger  ones  leading 
to  the  duct  of  the  testis,  or  the  ductus  deferens. 

The  ductus  deferens  passes  upward  from  the  testis  through  the 
subcutaneous  ring  and  the  inguinal  canal,  then  down  into  the  pelvis 
and  beneath  the  bladder,  where  it  runs  forward  to  enter  the  urethra. 

The  spermatic  cord. — The  testis  is  suspended  in  the  scrotum 
by  the  spermatic  cord,  which  reaches  from  the  abdominal  inguinal 
ring  to  the  bottom  of  the  scrotum,  and  contains  the  cremaster  muscle. 
Contraction  of  the  cremaster  muscle  lifts  the  testis  and  draws  it 
upward  in  the  scrotum  (Fig.  203). 

Descent  of  the  Testis. — During  fetal  life  the  testis  is  situated  in 
the  abdominal  cavity,  just  below  the  kidney,  but  it  slowly  descends 
to  pass  through  the  inguinal  canal,  reaching  the  subcutaneous  ring 
at  about  the  eighth  month,  and  at  birth  it  should  be  in  the  scrotum. 
It  may  descend  more  slowly,  or  may  be  arrested  at  any  point,  but 
usually  finds  its  place  in  time. 

In  the  scrotum  it  is  surrounded  by  a  double  sheath  of  the  peritoneum 
{tunica  vaginalis)  which  accompanied  it,  and  which  became  shut  oflf  from  the 
great  peritoneal  sac  as  the  subcutaneous  ring  closed  around  it. 

In  caring  for  the  male  infant  it  is  important  to  note  the  condition  of  the 
foreskin  (or  prepuce).  This  is  a  fold  of  skin  which  covers  the  glans  penis.  It 
should  be  sufficiently  loose  to  be  easily  drawn  back,  or  retracted,  in  order  that 
careful  cleansing  of  fhe  parts  may  prevent  accumulations  of  sebaceous  material, 
or  smegma.  If  this  is  not  done,  irritation  is  caused  by  retained  substances,  and 
also  by  adhesions  which  are  apt  to  form. 

Circumcision  is  cutting  off  the  foreskin  (literally — cutting  around). 


CHAPTER  XXII. 
A  BRIEF  STUDY  OF  IMPORTANT  REGIONS. 

THE  HEAD  AND  NECK. 

The  scalp. — Observe  the  larger  arteries — the  supraorbital  in 
front,  the  temporal  and  posterior  auricular  at  the  sides,  and  occipital 
at  the  back — that  their  general  course  is  upward  toward  the  vertex, 
and  therefore  a  bandage  may  be  so  adjusted  around  the  head  as  to 
cut  off  the  blood  supply  to  a  great  extent. 

The  nerves  have  similar  names  and  take  a  similar  course. 

The  tense  temporal  fascia  covers  the  temporal  muscle  above  the 
zygoma. 

The  Face. 

The  main  artery,  external  maxillary  (or  facial) ,  runs  obliquely 
upward  toward  the  side  of  the  nose;  its  course  is  tortuous,  so  that 

the  play  of  the  facial 
muscles  will  not  interfere 
with  the  passage  of  the 
blood  current.  The 
facial  vein  is  lateral  to 
the  artery  and  not  very 
close  to  it.  Pulsation  of 
the  artery  may  be  felt 
where  it  crosses  the  lower 
border  of  the  mandible, 
about  one  inch  in  front 
of  the  angle. 

The   external  carotid 
artery  bifurcates  in  the 

"f^g.  204.-SUPERPICIAL  Vessels^of  Head.  substance  of  the  parotid 

gland  in  front  of  the  ear, 
forming  the  temporal  and  internal  maxillary  arteries.  The  pulsation 
of  the  temporal  is  felt  as  it  crosses  the  zygoma,  and  both  here  and 

292 


THE  REGION  OF  THE  NECK.  293 

over  the  external  maxillary  on  the  border  of  the  mandible,  the 
character  of  the  heart's  action  may  be  appreciated  while  the  patient 
is  under  the  influence  of  ether. 

The  motor  nerves  (facial  nerve)  come  through  the  parotid  gland 
and  radiate  on  the  side  of  the  face,  transversely  toward  the  nose, 
upward  toward  the  eye  and  forehead,  and  downward  the  toward 
the  neck. 

Sensory  nerves,  branches  of  the  trifacial  {trigeminus) ,  appear  at 
the  three  foramina  mentioned  elsewhere — supraorbital,  infraorbital 
and  mental — the  three  particularly  sensitive  spots  in  the  front  of  the 
face. 

Practical  note. — The  tongue  muscles  and  the  floor  of  the  mouth 
{mylo-hyoid  muscle)  are  both  connected  with  the  mandible.  There- 
fore, if  the  jaw  be  held  forward  and  upward,  it  will  control  the  posi- 
tion of  the  tongue  when  the  muscles  are  relaxed,  as  under  ether. 
Hence,  the  necessity  for  this  precaution  to  prevent  the  tongue  from 
falling  back  into  the  throat. 

The  Neck. 

The  skin  of  the  back  of  the  neck  is  very  tough  and  X\yQ  fascia  very 
dense.  These  facts  account  for  the  pain  of  inflammation  here,  due 
to  the  consequent  pressure  upon  the  rather  numerous  nerves,  as  in 
carbuncle. 

The  spine  of  the  seventh  cervical  vertebra  is  always  easily  felt. 
This  is  the  vertebra  prominens. 

The  two  sterno-cleido-mastoid  muscles  are  conspicuous  at  the 
side  of  the  neck,  situated  near  each  other  at  their  origin,  and  diverg- 
ing above.  The  thyroid  cartilage  of  the  larynx  projects  in  front — - 
the  so-called  Adam's  apple.  The  external  jugidar  vein  runs  from 
behind  the  ear  downward,  toward  the  middle  of  the  clavicle,  and  is 
covered  by  the  platysma  muscle.  It  is  sometimes  selected  for  the 
operation  of  "bleeding,"  or  phlebotomy,  and  the  incision  to  expose 
the  vein  is  made  across  the  muscle  fibers,  because  by  their  retraction 
the  vessel  is  well  uncovered  (Fig.  71,  p.  ^T)). 

The  sternomastoid  and  trapezius  are  the  muscles  affected  in  the 
commonest  form  of  wry-neck  or  torticollis,  which  is  usually  due  to 
spasm  of  the  muscles. 


294 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


The  Triangles  of  the  Neck  (Fig.  205). 


These  are  spaces  between  certain  muscles,  as  follows:  In  front 
of  the  sterno-mastoid  is  an  anterior  triangle  divided  by  the  superior 
belly  of  the  omo-hyoid  into  two,  called  the  carotid  and  muscular 
triangles ;  behind  the  sterno-mastoid  is  a  posterior  triangle  divided 
by  the  inferior  belly  of  the  omo-hyoid  into  two,  called  the  occipital 
and  subclavian  triangles. 


Fig.  205. — Triangles  of  the  Neck. 
C,  Carotid  triangle;  M,  muscular  triangle;  O,  occipital  triangle;  S,  subclavian  triangle; 

D,  digastric  triangle. 


In  the  muscular  triangle  is  the  common  carotid  artery,  with  the 
internal  jugular  vein  on  the  lateral  side  of  it,  and  the  vagus  nerve 
behind  them  both. 

In  the  carotid  triangle  the  same  structures  are  found,  but 
here  the  artery  divides,  forming  the  external  and  internal  carotid 
arteries  at  about  the  level  of  the  upper  border  of  the  thyroid  cartilage, 
or  Adam's  apple. 

Surgical  note. — The  carotid  is  called  the  triangle  of  election  because,  since 
the  vessels  are  near  the  surface,  the  surgeon  would  naturally  choose,  or  elect, 
this  place  for  the  operation  of  ligation.     In  the  muscular  triangle  the  vessels 


THE    THORAX.  295 

are  more  deeply  placed  and  covered  by  the  lower  portion  of  the  sterno-mastoid. 
Ligation  of  the  artery  would  be  done  here  only  under  necessity,  so  it  is  called  the 
triangle  of  necessity. 

Occipital  triangle. — The  occipital  artery  and  nerve  run  through 
this  triangle. 

Subclavian  triangle. — Most  important  structures  are  sub- 
clavian artery  and  vein,  brachial  plexus,  and  phrenic  nerve. 

Clinical  note. — Pressure  in  this  triangle,  close  to  the  clavicle,  will  be  felt  by 
the  nerves  of  the  brachial  plexus.  Pressure  downward  and  backward  close  to 
the  sterno-mastoid  will  compress  the  subclavian  artery  against  the  first  rib.  Its 
pulsation  is  plainly  felt. 

Submaxillary  triangle. — This  is  a  small  space  marked  off  from  the  carotid 
by  the  digastric  muscle.  It  contains  the  submaxillary  gland  and  external  maxil- 
lary artery. 

The  Thorax  and  Thoracic  Viscera. 

The  bony  thorax  is  narrow  above  and  broad  below,  but  the 
proportions  are  reversed  in  the  completed  human  body  by  the 
presence  of  the  large  muscles  which  connect  the  upper  extremity  to 
the  thorax. 

Observe  the  transverse  ridge  on  the  sternum,  marking  the  junction 
of  the  first  and  second  pieces  (the  manubrium  and  the  body) ,  The 
second  rib  joins  the  sternum  at  this  ridge  (Fig.  206). 

The  boundaries  of  the  completed  thorax  are  the  spinal  column 
at  the  back,  the  sternum  in  front,  and  the  ribs  at  the  sides,  with  the 
intercostal  muscles  in  the  intercostal  spaces  and  the  diaphragm  in 
the  floor.  It  is  covered  behind  by  the  muscles  of  the  back,  while  the 
anterior  serratus  is  on  the  side  and  the  pectoral  muscles  are  in  front. 
The  shoulder-blades  are  placed  behind  the  thorax. 

The  intercostal  arteries  and  nerves  are  protected  from  injury  by 
their  position  under  the  borders  of  the  ribs.  A  stab-wound  would 
have  to  be  directed  upward  to  reach  them. 

All  muscles  which  are  attached  to  the  ribs  are  muscles  of  res- 
piration, the  intercostals  having  considerable  power,  but  the  dia- 
phragm being  most  important.  When  it  contracts  it  is  depressed, 
increasing  the  depth  of  the  thoracic  cavity,  while  the  other  muscles 
broaden  the  cavity  by  lifting  the  ribs,  and  thus  room  is  made  for 
expansion  of  the  lungs  in  inspiration.  As  the  ribs  fall  and  the 
diaphragm  ceases  to  contract,  it  rises,  returning  to  its  dome  shape, 


296 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


and  thus  the  air  is  pressed  from  the  lungs  in  expiration.  These 
two  acts  complete  a  respiration,  or  an  act  of  breathing,  which  occurs 
normally  about  eighteen  times  in  a  minute.  If  respiration  is  very 
difficult  other  muscles  are  called  into  play,  as  in  asthma,  when  the 
struggle  for  breath  is  so  great  that  "forced  inspiration"  is  necessary. 
The  erector  spinge  muscles  are  always  on  duty,  to  steady  the 
spine  in  order  that  the  ribs  may  have  a  point  of  departure. 


Fig.  206. — Thoracic  and  Abdominal  Viscera,  Anterior. 

The  cardiac  impulse  is  felt  (sometimes  it  may  be  seen)  between 
the  fifth  and  sixth  ribs,  half  way  between  the  sternum  and  the 
nipple  line. 

The  mammary  gland  covers  the  front  part  of  the  spaces  from  the 
third  to  the  fifth  ribs.  It  lies  between  layers  of  the  superficial  fascia 
in  front  of  the  pectoralis  major  muscle. 

The    superior   opening   transmits    the    trachea,    esophagus,    and 


THE   ABDOMEN.  297 

important  vessels  and  nerves.  The  floor  (or  diaphragm)  has  three 
openings — one  for  the  passage  of  the  aorta  and  thoracic  duct,  one  for 
the  inferior  vena  cava,  and  one  for  the  esophagus  and  vagus  nerves. 

The  thoracic  viscera  are  the  esophagus,  trachea  and  bronchi, 
lungs,  and  heart.  The  esophagus  lies  close  to  the  spinal  column,  and 
the  trachea  is  in  front  of  the  esophagus,  dividing  into  the  large 
bronchi,  whose  branches  are  the  bronchial  tubes.  The  heart  and 
large  vessels  are  in  the  anterior  and  middle  part  of  the  thoracic 
cavity  (Fig.  206). 

The  heart  is  wrapped  in  the  pericardium,  and  each  lung  is 
wrapped  in  a  pleural  sac  which  is  placed  between  the  lung  and  the 
chest  wall.  An  incision  through  that  part  of  the  wall  which  is 
bounded  by  the  ribs  would  pierce  the  costal  pleura  and  open  the 
pleural  cavity.  A  wound  of  the  lung  would  injure  the  pulmonary 
pleura  (Fig.  152). 

The  large  nerves  in  the  thoracic  cavity  are  the  vagi,  lying  close 
to  the  esophagus,  the  sympathetic,  whose  branches  form  cardiac 
and  pulmonary  plexus,  and  the  two  phrenic  nerves,  right  and  left, 
running  down  on  either  side  of  the  pericardium  to  the  diaphragm. 

The  mediastinum  is  the  space  between  the  lungs.  In  it  all  of 
the  thoracic  viscera  except  the  lungs  are  situated. 

The  Abdomen,  Abdominal  Visceil\,  and  Peritoneum. 

The  boundaries  of  the  completed  abdomen  are  the  spinal 
column  and  quadratus  lumborum  muscles  at  the  back,  the  hip-hones 
below,  the  rectus  muscles  in  front,  and  the  hroadjlat  muscles  at  the 
side.  The  diaphragm  is  its  roof.  The  transversalis  fascia  lines  the 
cavity,  and  the  peritoneum  is  within  the  fascia,  held  to  it  by  areolar 
tissue  called  subperitoneal  or  subserous  tissue. 

On  the  anterior  surface  of  the  abdomen  observe  the  outline 
made  by  the  lower  ribs,  between  the  thorax  and  abdomen,  the  two 
sides  meeting  in  the  subcostal  angle  just  below  the  sternum.  The 
scrobiculus  cordis,  or  pit  of  the  stomach,  is  a  slight  depression  at  the 
very  point  of  the  subcostal  angle,  caused  by  a  weak  spot  in  the 
attachment  of  the  abdominal  muscles.  If  the  abdomen  is  distended, 
the  depression  disappears.  The  linea  alba  is  between  the  two  rectus 
muscles,  and  the  semilunar  lines  (or  linece  semilunares)  arc  at  the  sides 
of  the  recti.  The  transverse  lines  {linea  transversce)  may  be  seen 
when  the  recti  contract. 


298 


ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 


The  subcutaneous  inguinal  ring  is  just  above  the  tubercle  of  the 
pubic  bone;  the  abdominal  inguinal  ring  is  a  half  inch  above  the 
middle  of  the  inguinal  ligament.  The  conjoined  tendon  is  behind  the 
subcutaneous  ring. 

The  abdominal  muscles  and  skin  are  supplied  by  the  lower  inter- 
costal and  first  lumbar  nerves. 

The  regions  of  the  abdomen  are  outlined  in  the  following 
manner:  Imagine  a  horizontal  plane  passing  through  the  abdomen 
at  the  level  of  the  tenth  costal  cartilage,  and  another  at  the  level 
of  the  anterior  superior  spine  of  the  ilium.     These  would  divide 


Tip  of  ensiform  cartilage 
Costal  border 


Upper  horizontal  plane 


Lower  horizontal  plane  A,  at 
level  of  tubercles  of  iliac 
crest 

Lower  horizontal  plane  B,  at 
evel  of  anterior  Uiac  spines 


Vertical  plane  A,  from  middle 
of  Poupart's  ligament 

\'ertical  plane  B,  at  outer  _ 
border  of  rectus  (semi- 
lunar line) 

Summit  of  symphysis  pubis 


Fig.  207. — Diagram  of  the  Abdominal  Regions  (Morris). 


it  into  three  portions — upper,  middle,  and  lower.  Then  imagine 
two  vertical  planes  passing  through  the  middle  point  of  the  inguinal 
ligament  on  either  side,  and  dividing  each  of  these  three  portions 
into  three  regions,  making  nine  in  all. 

The  middle  region  is  called  the  umbilical,  having  the  umbilicus 
on  the  anterior  surface.  Above  that  is  the  epigastric,  and  below  it 
is  the  hypogastric.  At  the  sides  of  the  epigastric  region  are  the 
right  and  left  hypochondriac.  At  the  sides  of  the  umbilical  region 
are  the  right  and  left  lumbar;  and  at  the  sides  of  the  hypogastric 
region  are  the  right  and  left  iliac,  or  inguinal. 


THE    PERITONEUM.  299 

The  abdominal  viscera  are  the  stomach,  intestines,  liver,  spleen, 
pancreas,  kidneys,  and  adrenal  bodies.  The  great  vessels  are  at  the 
back.  The  sympathetic  ganglia  are  at  the  sides  of  the  vertebrae, 
with  the  celiac  and  other  plexuses  situated  on  the  large  vessels. 

The  kidneys  are  behind  all  of  the  other  viscera,  and  the  ureters 
run  down  close  to  the  posterior  wall  of  the  abdomen  on  their  way  to 
the  bladder. 

The  receptaculum  chyli,  or  beginning  of  the  thoracic  duct,  is  in 
front  of  the  second  lumbar  vertebra.  The  inferior  vena  cava  lies  on 
the  right  side  of  the  aorta. 

The  principal  organ  in  the  epigastric  region  is  the  stomach;  in 
the  right  hypochondriac,  the  liver;  in  the  left  hypochondriac,  the  spleen. 
The  umbilical  region  is  occupied  mostly  by  small  intestines.  The 
right  and  left  kidneys  are  in  the  two  lumbar  regions,  with  the  ascending 
colon  in  front  of  the  right,  and  the  descending  colon  in  front  of  the  left 
kidney.  The  cecum  and  appendix  are  in  the  right  inguinal  region; 
the  bladder,  in  the  hypogastric. 

Each  region  contains  portions  of  several  viscera  in  addition  to  those  named. 
Scarcely  any  organ  save  the  spleen  and  cecum  can  be  said  to  belong  to  but  one 
region. 

The  peritoneum  is  a  closed  sac  of  serous  membrane  like  a 
water-bag,  which  is  placed  between  the  abdominal  wall  and  abdom- 
inal viscera.  It  is  practically  in  front  of  the  viscera,  and  tucked  in 
around  them  at  the  sides.  One  side  of  the  sac  is  closely  applied  to 
the  abdominal  wall,  and  is  called  the  parietal  peritoneum,  while  the 
other  side  is  fitted  to  the  viscera,  and  called  the  visceral  peritoneum. 
Normal  peritoneum  is  perfectly  transparent,  and  the  viscera  are 
plainly  seen  through  the  visceral  layer.  The  peritoneal  cavity  con- 
tains a  little  serous  fluid  and  nothing  else. 

An  incision  in  the  abdominal  wall,  including  the  parietal  perito- 
neum, opens  the  peritoneal  cavity.  An  incision  into  one  of  the 
organs  involves  the  visceral  peritoneum,  with  these  exceptions : 

The  posterior  surface  of  the  liver. 

The  posterior  surface  of  the  ascending  colon.     The  kidneys. 

The  transverse  portion  of  the  duodenum.  The  front  of  the 
bladder  behind  the  symphysis.     These  parts  have  no  serous  layer. 

The  lowest  portion  of  the  peritoneal  cavity  is  in  the  pelvis, 
extending  down  about  three  and  a  half  inches  in  front  of  the  rectum. 


300  ANATOMY  AND    PHYSIOLOGY   FOR   NURSES. 

In  the  female  this  is  called  the  recto-uterine  fossa,  or  pouch  of  Douglas 
In  the  male  it  is  the  recto-vesical  fossa. 

The  folds  of  the  peritoneum  which  are  connected  with  the  stomach 
are  called  omenta  (p.  137). 

The  folds  which  connect  the  intestines  to  the  abdominal  wall 
are  called  mesenteries  (p.  137). 

The  folds  which  connect  other  organs  to  the  abdominal  or  pelvic 
walls  are  called  ligaments.  Those  for  the  bladder  are  called 
vesical  ligaments. 

The  ligaments  of  the  liver  are  the  broad,  the  round,  the  coronary, 
and  the  two  lateral  ligaments,  which  connect  it  to  the  diaphragm 
and  the  anterior  abdominal  wall. 

Sometimes  certain  little  pockets,  or  fossae,  exist  in  the  peritoneum, 
behind  the  different  portions  of  intestine.  If  a  loop  or  knuckle  of 
bowel  slips  into  one  of  these  fossae  it  may  press  its  way  through  it 
and  pass  behind  the  peritoneal  sac.     This  is  a  retro-peritoneal  hernia. 

The  Ischio-rectal.  Fossa. 

This  is  a  space  between  the  ischium  and  the  rectum.  It  is  filled 
with  loose  connective  tissue  and  adipose,  and  a  few  vessels  and 
nerves  are  therein  contained.  The  skin  of  the  buttock  forms  the 
floor  of  the  fossa;  the  lower  part  of  the  rectum  is  the  medial  wall; 
the  fascia  of  the  obturator  muscle  forms  the  lateral  wall. 

Surgical  note. — If  infection  occur  in  this  region,  a  very  large  abscess  might 
result,  the  pus  burrowing  freely  in  the  loose  tissues.  Ischio-rectal  abscess  is 
often  caused  by  internal  fistula. 

The  Axillary  Space. 

The  axilla  is  the  armpit.  Its  shape  is  that  of  a  pyramid,  with 
the  apex  under  the  shoulder-girdle  at  the  level  of  the  first  rib,  the 
base  of  the  pyramid  being  the  floor  of  the  space  and  composed  of  the 
skin  and  fascia  crossing  from  the  thorax  to  the  arm.  The  walls  of 
the  space  are  formed  by  muscles — the  serratus  (principally)  on  the 
medial  wall,  covering  the  ribs;  the  long  tendon  of  the  biceps  in  its 
groove  on  the  lateral  wall;  the  pectoral  muscles  in  the  anterior  wall, 
and  the  subscapularis,  latissimus  dorsi  and  teres  major  in  the  poste- 
rior wall. 

The  importance  of  this  space  is  due  to  the  large  vessels  and 


THE    FEMORAL    TRIGONE. 


301 


nerves,  and  the  lymph  nodes,  which  are  found  in  it.  The  vessels 
are  the  axillary  artery  and  vein;  the  ners^es  are  the  brachial  plexus 
and  branches.  A  chain  of  superjicial  lymph  nodes  lies  under  the 
border  of  the  pectoralis  major,  and  a  collection  of  deep  ones  is 
grouped  around  the  large  vessels;  there  are  also  a  few  near  the 
posterior  wall. 

The  Ante-cubital  Space. 

A  triangular  space  in  front  of  the  elbow-joint. 
Boundaries. — The     hrachio-radialis,    pronator    teres,    and     an 
imaginary  line  connecting  the  two  epicondyles. 

Important  structures. — Biceps  tendon,  brachial  artery  and  veins, 
median  nerve.     The  artery  is  between  the  tendon  and  the  nerve, 
Axillary  artery  Ijing  on  the  brachialis  mus- 

cle. Tendon  on  lateral  side 
of  artery — T-endon,  A-rtery, 
N-erve.  The  artery  divides 
here. 


Median  nerve 
Brachial  artery 


Lateral  cord 


Fig.  208. — Axillary  Space. 

Axilla  laid  open  by  division  of  anterior 

wall. 


Fig.  209. — Ante-cubital  Space. 

Pronator  muscle  divided  to  show 

ulnar  artery. 


Scarpa's  Triangle  (Trigonum  Femorale). 

This  triangle  is  on  the  front  of  the  thigh.  The  base  is  formed 
by  the  inguinal  ligament,  the  lateral  border  by  the  upper  half  of  the 
sartorius,  the  medial  border  by  the  adductor  longus,  and  the  apex  by 
the  crossing  of  these  two  muscles  on  the  medial  side  of  the  thigh  at 
about  the  middle. 

The  most  important  structures  in  the  triangle  are  the  femoral 
artery  and  vein  lying  side  by  side,  in  a  line  from  the  middle  of  the 


302 


ANATOMY  AND    PHYSIOLOGY    FOR    NURSES. 


base  to  the  apex.     The  femoral  nerve  and  branches  are  to  the 
lateral  side  of  the  artery. 

Order  of  structures  as  they  pass  under  the  inguinal  ligament: 
V-ein,  A-rtery,  N-erve,  the  vein  being  medialward. 

Hunter's  Canal  (Adductor  Canal). 

This  is  a  passage  from  the  front  of  the  thigh  around  the  medial 
side  to  the  posterior,  beginning  at  the  apex  of  Scarpa's  triangle  and 
ending  in  the  popliteal  space  by  an  opening  in  the  adductor  magnus 
muscle.  The  femoral  artery  passes  through  this  canal,  with  the 
femoral  vein  on  the  medial  side  of  the  artery.  The  long  saphenous 
nerve  is  sometimes  within  the  canal  and  sometimes  outside  it. 


Femoral  artery 
Femoral  nerve 

Feraoral  vein 


Deep  branch 


Fig.  2IO. — Structures  in 
Scarpa's  Triangle;  portion  of 
Sartorius  removed. 


Fig.  211. — Popliteal  Space  (Holden). 

a,  Biceps;  h,  peroneal  nerve;  c,  plantaris; 

d,    lateral   head   of   gastrocnemius;   e,  semi- 

tendinosus; /,  semimembranosus;  g,  gracilis; 

h,  sartorius;  i,  medial  head  of  gastrocnemius. 


The  Popliteal  Space. 
This  is  a  deep  diamond-shaped  space  behind  the  knee-joint. 
Itsjloor  is  formed,  from  above  downward,  by  the  popliteal  surface  of 


INGUINAL  AND    FEMORAL   CANALS.  3O3 

the  femur,  the  posterior  ligament  of  the  joint,  and  the  popliteus 
muscle.  The  boundaries  of  the  upper  half  of  the  space  are  made  by 
the  biceps  tendon  on  the  lateral  side,  and  the  semitendinosus  and 
semimembranosus  on  the  medial  side.  The  boundaries  of  the  lower 
half  are  the  lateral  and  ynedial  heads  of  the  gastrocnemius.  These 
muscles  are  all  very  prominent,  making  the  space  deep.  The 
popliteal  space  owes  its  importance  to  the  large  vessels  and  nerves 
which  it  contains — the  popliteal  artery,  the  popliteal  vein,  and  tibial 
and  common  peroneal  nerves.  They  are  all  deeply  situated,  the  artery 
being  the  deepest,  and  are  imbedded  in  adipose  tissue  and  covered 
with  strong  fascia,  being  thus  well  protected. 

The  Inguinal  Rings  and  Inguinal  Canal. 

There  is  an  opening  in  the  aponeurosis  of  the  external  oblique 
muscle  just  above  the  pubic  bone,  which  is  called  the  subcutaneous 
inguinal  ring,  being  under  the  skin  in  the  inguinal  region. 

There  is  an  opening  in  the  transversalis  fascia,  half  an  inch 
above  the  mid-point  of  the  inguinal  ligament.  This  is  called  the 
abdominal  inguinal  ring,  opening  into  the  abdominal  cavity  in 
the  inguinal  region.  The  passage  from  one  ring  to  the  other  is  the 
inguinal  canal. 

The  internal  oblique  and  transversus  muscles  form  the  conjoined 
tendon  immediately  behind  the  subcutaneous  ring,  and  their  lower 
muscle  fibers  arch  over  the  canal,  forming  its  upper  boundary. 

The  Femoral  Ring  and  Femoral  Canal. 

The  femoral  ring  {annulus femorale)  is  a  weak  place  in  the  pelvic 
wall,  under  the  inguinal  ligament,  where  the  femoral  vessels  do  not 
occupy  the  whole  of  the  space  in  their  sheath.  It  is  on  the  medial 
side  of  the  vein,  bounded  medially  by  Gimbernat's  ligament  (which  is 
at  the  medial  extremity  of  the  inguinal  ligament)  and  closed  by 
transversalis  fascia  only,  which  at  this  spot  is  called  the  crural  septum 
{septum  crurale). 

The  femoral  canal  extends  downward  from  this  ring  about 
three-quarters  of  an  inch  in  the  sheath  of  the  femoral  vessels. 

Hernia. 

Hernia  is  defined  as  a  tumor  formed  by  the  protrusion  of  con- 
tents of  a  cavity  through  its  wall.     This  may  occur  at  any  weak  place 


304  ANATOMY  AND   PHYSIOLOGY   FOR   NURSES. 

in  the  wall,  but  is  most  frequent  in  the  region  of  the  inguinal  or 
femoral  canals. 

If  any  structure  slips  accidentally  through  the  inguinal  canal  it 
forms  an  inguinal  hernia,  which  most  commonly  contains  a  loop 
of  bowel.  To  replace  the  bowel  or  other  structure  is  to  reduce  the 
hernia.  If  the  loop  cannot  be  replaced,  the  hernia  is  irreducible; 
and  should  it  become  so  distended  as  to  interfere  with  the  circulation, 
it  will  be  strangulated. 

In  direct  inguinal  hernia  the  contents  of  the  tumor  have  passed 

directly  through  the  conjoined  tendon  and  subcutaneous  ring.     In 

indirect  inguinal  hernia  the  contents  of  the  tumor  have  passed 

through  the  whole  length  of  the  inguinal  canal — that  is,  first  the 

abdominal  ring,  then  the  canal,  then  the  subcutaneous  ring. 

Umbilical  hernia  occurs  at  the  umbilicus;  ventral  hernia  at 
any  other  part  of  the  abdominal  wall,  except  one  or  both  rings. 

Diaphragmatic  hernia  occurs  at  a  weak  or  defective  point  in 
the  diaphragm  where  an  abdominal  structure  may  press  its  way  into 
the  thorax. 

In  femoral  hernia  the  bowel  or  other  organ  passes  through  the 
femoral  ring  into  the  femoral  canal  and  pushes  its  way  through  the 
femoral  sheath  at  the  oval  fossa,  or  saphenous  opening. 

The  Extremities  Compared. 

Both  extremities  are  servants  of  the  head  and  trunk.  The  lower ^ 
being  fashioned  for  bearing  weight  and  also  for  walking  or  running, 
are  organs  of  locomotion,  transporting  the  body  from  place  to  place 
as  necessity  or  convenience  may  dictate;  while  the  upper  are  organs  of 
prehension,  since  they  can  reach  forth  and  secure  various  things 
which  are  required  for  the  use  of  the  body. " 

Flexion  of  the  arm  is  accomplished  by  a  two-headed  muscle — 
the  biceps;  flexion  of  the  thigh  by  a  double  muscle,  the  ilio-psoas. 
Extension  of  the  elbow  is  accomplished  by  a  three-headed  muscle, 
the  triceps;  extension  of  the  knee  requires  a  powerful  four-headed 
muscle,  the  quadriceps. 

We  have  learned  to  apply  the  terms  medial  and  lateral  to  the  body 
while  in  the  anatomical  position,  in  which  the  forearm  is  supinated; 
therefore  the  thumb  is  said  to  be  on  the  lateral  border  of  the  hand, 
but  the  leg  cannot  be  supinated,  and  the  great  toe  lies  on  the  medial 
border  of  the  foot. 


THE   EXTREMITIES   COMPARED. 


305 


Observe  that  the  toes  of  civilized  man  are  freely  flexed  and  ex- 
tended, but  have  no  other  independent  motions.  They  are  slightly 
affected  by  the  action  of  plantar  muscles,  but  the  foot  has  lost  the 
suppleness  it  might  have  had  without  wearing  shoes.  The  fingers, 
however,  can  all  be  moved  sideways;  the  median  line  of  the  hand  is 
a  line  drawn  to  the  tip  of  the  middle  finger,  and  the  digits  are  said  to 
be  abducted  or  adducted,  according  as  their  motion  is  from  or 
toward  this  line. 

The  freedom  and  mobility  of  the  thumb  add  very  greatly  to  the 
usefulness  of  the  hand  in 
grasping,  carrying,  etc.  If 
the  finger  tips  approach 
each  other,  the  hand  falls 
into  a  gently  curved  posi- 
tion forming  a  cup,  the 
"cup  of  Diogenes."  If 
the  hand  be  closed  forcibly 
with  the  thumb  holding  the 
fingers  against  the  palm, 
it  becomes  a  solid  irregular 
mass,  the  "fist,"  and  so  an 
ever-available  weapon  of 
offense  or  defense. 

The  shoulder  (and 
whole  upper  extremity)  is 
pidled  forward  by  the  action 
of  the  anterior  serratus  on 
the  shoulder  blade,  and  if 
this  motion  is  accompanied 
by  a  sudden  forcible  exten- 
sion of  the  arm  and  forearm,  that  is  "  striking  out  from  the  shoulder.' 


Ulnar  nerve  and  artery 
Radial  nerve  and 
artery- 


Branches  to  hand 


Fig.  212. — The  Forearm,  Anterior. 


Review  Notes  Concerning  the  Extremities. 

The  upper  extremity — ^From  the  shoulder  down,  the  anterior 
surface  is  xYieflexor  surface,  and  the  posterior  is  the  extensor  surface  of 
the  extremity. 

Arm.  Anterior. — The  biceps  muscle,  with  the  median  nerve  and 
brachial  vessels  on  its  medial  border.  Posterior. — Triceps  muscle, 
with  radial  nerve  in  the  groove  between  the  two  humeral  heads. 


3o6 


ANATOMY   AND    PHYSIOLOGY    FOR   NURSES. 


Suprascapular  nerve  and  artery 


Forearm.     Anterior  (Fig.  212). — Superficial  jiexor  muscles  and 

the  round  pronator  from  the 
internal  epicondyle.  Deep  flexor 
muscles  from  shafts  of  the  radius 
and  ulna,  and  median  nerve  be- 
tween the  superficial  and  deep 
groups.  Posterior. — Extensor 
muscles  and  the  short  supinator 
from  the  external  epicondyle. 
Lateral  or  radial  side,  hrachio- 
radialis  from  the  external  epi- 
condylar  ridge. 

The  hand.  Palm. — Observe 
the  thenar  eminence  of  thumb 
muscles;  the  hypothenar  emi- 
nence of  little-finger  muscles, 
and  between  them  the  hollow  of 
the  hand,  where  the  long  flexor 
tendons  lie.  The  deep  palmar 
arch  is  underneath  the  tendons; 
the  superficial  arch  lies  upon 
them;  the  strong  palmar  fascia 
holds  the  tendons  in  a  compart- 
ment lined  with  synovial  mem- 
brane. Dorsum. — The  extensor 
tendons  are  plainly  seen.  The 
radial  artery  may  be  felt  in  the 
"anatomic  snuff-box"  (between 
two  of  the  extensors  of  the 
thumb  as  it  winds  around  the 
first  metacarpal  bone  to  reach 
the  deep  palm)  (Fig.  212). 

The  long  flexor  and  extensor 
tendons  of  the  fingers  may  be 
plainly  felt  and  seen  at  the  wrist. 


Deep 

branch 


Posterior 
interosseous 


Fig. 


213. — The  Arm  and  Forearm, 
Posterior. 


The   lower  extremity. — The 
inguinal  ligament  stretches  from 
the  spine  of  the  ilium  to  the  tubercle  of  the  pubes. 


THE    THIGH.       THE    LEG.  307 

The  femoral  artery,  femoral  vein,  2ind  femoral  nerve  pass  under  the 
ligament,  the  artery  lying  on  the  psoas  muscle.  Their  order  from 
the  medial  side  outward  is  V-ein,  A-rtery,  N-erve. 


From  the  hip  down,  the  anterior  surface  is  al- 
ternately j?exor  and  extensor 


The  posterior  surface  is  exactly  the  reverse . 


Flexor  for  hip. 
Extensor  for  knee. 
Flexor  for  ankle. 
Extensor  for  toes. 

Extensor  for  hip. 
Flexor  for  knee. 
Extensor  for  ankle. 
Flexor  for  toes. 

Thigh. — Anterior  and  sides  of  the  femur  are  covered  by  the 
quadriceps  muscle,  which  extends  the  knee.  The  sartorius  muscle 
crosses  from  the  anterior  spine  of  the  ilium  to  the  middle  of  the 
medial  side  of  the  thigh  and  down  to  the  tibia,  and  when  it  contracts 
it  makes  a  depression  rather  than  an  elevation,  because  it  binds  the 
soft  tissue  under  it.  Posterior. — The  biceps,  semimembranosus  and 
semitendinosus  muscles  flex  the  knee;  they  are  hamstring  muscles, 
making  the  upper  boundaries  of  the  popliteal  space.  The  medial 
side  of  the  thigh  is  occupied  by  the  adductor  muscles,  with  the  obtu- 
rator nerve  and  vessels. 

Leg.  Anterior. — The  medial  surface  of  the  tibia  is  called  sub- 
cutaneous because  it  is  not  covered  by  muscles;  the  long  saphenous 
nerve  and  vein  extend  the  whole  length  of  this  surface. 

The  anterior  tibial  muscles  occupy  the  neighboring  surfaces  of  the 
tibia  and  fibula,  and  their  tendons  all  pass  in  front  of  the  ankle-joint 
Xoflex  it  (dorsal  flexion).  The  lateral  side  of  the  leg  is  occupied  by 
the  peroneus  longus  and  brevis  whose  tendons  pass  behind  the  lateral 
malleolus  to  extend  the  foot.  They  are  accompanied  by  the  super- 
ficial peroneal  nerve  which  supplies  them  (ant.  tibial  nerve). 

The  long  tendons  for  the  toes  are  plainly  visible  on  the  dorsum 
or  top  of  the  foot,  and  also  those  of  the  short  flexor,  which  has  four 
tendons  belonging  to  the  four  medial  toes. 

Posterior. — The  calf  muscles,  which  lift  the  heel,  completely 
cover  the  deep  muscles  whose  tendons  pass  into  the  sole  of  the  foot 
behind  the  medial  malleolus  to  extend  the  foot. 

The  deep,  or  posterior  tibial  muscles,  lie  between  tibia  and  fibula 
bound  down  by  the  deep  transverse  fascia  of  the  leg. 


3o8 


ANATOMY  AND    PHYSIOLOGY    FOR   NURSES. 


Femoral 
nerve 

Femoral 
"f,  /       /  artery 

i^K    /  Femoral 

Ml/.    J vein 


Anterior  tibial 
nerve 


Anterior  tibial 
artery 


Sciatic  nerve 


Peroneal  nerve 


Ant.  tib.  artery 


Tibial  nerve 
Post.  tib.  artery 


Fig.  214. — The  Femoral  Artery.  Fig.  215. — The  Sciatic  Nerve 


VESSELS  AND    NERVES    OF    EXTREMITIES.  309 

The  large  nen^es  for  the  lower  extremity  are  the  femoral  and 
the  sciatic. 

The  femoral  comes  under  the  inguinal  ligament  into  Scarpa's 
triangle  and  immediately  breaks  up  into  branches  which  supply 
the  structures  of  the  thigh,  the  long  saphenmis  nerve  being  the  only 
branch  to  go  below  the  knee.  It  runs  all  the  way  to  the  medial 
border  of  the  foot. 

The  sciatic  comes  through  the  great  sciatic  notch,  descending 
between  the  great  trochanter  and  the  tuber  of  the  ischium  into  the 
back  of  the  thigh,  to  divide  into  the  tibial  and  the  common  peroneal 
nerves.  The  tibial  nerve  continues  under  the  calf  muscles  and  into 
the  plantar  region.  The  peroneal  nerve  winds  around  the  head  of  the 
tibia  to  the  front  of  the  leg,  sending  the  deep  peroneal  branch  to  the 
anterior  muscles,  and  dorsum  of  the  foot. 

Location  of  Large  Vessels  and  Nerves  in  the 
Extremities. 

The  vessels  and  nerves  are  so  placed  as  to  be  in  the  least  possible 
danger  from  pressure  or  blows.  For  example,  the  axillary  vessels 
and  brachial  plexus  are  deep  in  the  axilla;  the  brachial  vessels  and 
median  and  ulnar  nerves  are  on  the  less  exposed  side  of  the  arm,  and 
they  pass  in  front  of  the  elbow- joint  where  the  motion  of  the  joint 
will  not  interfere  with  them.  So  in  the  forearm,  the  radial  and 
ulnar  arteries  and  nerves  are  protected  by  muscles.  At  the  wrist 
they  also  pass  into  the  hand  on  ih.t  flexor  surface. 

The  large  nerve  which  passes  behind  the  humerus,  the  radial 
nerve,  is  covered  by  the  thick  triceps  muscle  and  winds  to  the  front 
of  the  bone  to  pass  the  elbow-joint  on  its  way  to  the  forearm. 

The  femoral  vessels  and  nerves  are  in  the  fold  or  flexure  of  the 
groin,  and  they  wind  around  the  femur  to  reach  the  flexor  surface 
of  the  knee.  Both  anterior  and  posterior  tibial  arteries  are  well 
protected  by  muscles — the  posterior  tibial  especially — which  is  under 
the  calf  muscles  and  the  transverse  fascia  of  the  leg.  As  it  passes  the 
ankle-joint  it  lies  under  strong  ligaments  on  the  medial  side  of  the 
joint,  where  is  would  not  be  put  on  the  stretch  during  any  natural 
motion  of  the  foot  nor  exposed  to  blows.  Again,  the  large 
arteries  of  the  hand  are  in  the  palm,  while  those  of  the  foot  are 
in  the  sole.  * 


3io  anatomy  and  physiology  for  nurses. 

Points  for  Compression  of  Larger  Arteries. 

The  temporal,  on  the  zygoma. 

The  external  maxillary,  on  the  lower  border  of  the  mandible. 

The  subclavian  on  the  first  rib,  behind  the  clavicle  (downward 
and  backward). 

The  axillary,  on  the  humerus,  in  the  lower  part  of  the  axilla. 

The  brachial,  on  the  humerus,  under  medial  border  of  the  biceps 
muscle. 

The  radial  and  ulnar,  on  the  bones  of  same  name,  in  the  lower 
part. 

The  femoral,  against  the  ramus  of  the  pubic  bone,  just  below 
the  inguinal  ligament. 

Note. — The  subclavian  artery  is  crossed  by  the  scalenus  anticus 
muscle  which  divides  it  into  first,  second,  and  third  portions.  The 
axillary  artery  is  crossed  by  the  pectoralis  minor  muscle,  which  divides 
it  into  first,  second,  and  third  portions.  The  common  carotid 
artery  is  crossed  by  the  omo-hyoid  muscle;  the  portion  below  the 
muscle  is  in  the  muscular  triangle  of  the  neck;  the  portion  above  is 
in  the  carotid  triangle. 


CHAPTER  XXIII. 
REFERENCE  TABLES. 


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CAROTIS    EXTERNA    AND 
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319 


GLOSSARY 


Abdomen.     From  a  word  meaning  to  conceal.     The  aVjclomen  contains  or  conceals  the 

abdominal  organs. 
Abduction.     From  a  Latin  word  meaning  to  lead  from.     The  abducens  muscle  leads,  or 

turns,  the  eye  from  the  median  line. 
Acetabulum.     A  small  vessel  or  cup  for  vinegar.     The  name  given  to  the  round 

depression  or  cavity  of  the  hip  bone  or  os  coxae,  for  the  head  of  the  femur. 
Acid.     Sour.     Acids  redden  blue  litmus  paper. 

Accommodation.     The  adjusting  or  focussing  of  the  eye  for  vision  at  different  distances. 
Acromegaly.     A  disease  characterized  by  over-growth  of  the  face  and  extremities. 
Acromion.     From  Greek  words  meaning  summit  and  shoulder.     The  process  of  bone 

at  the  highest  point  of  the  shoulder. 
Adduction.     Leading  toward. 

Adenoid.     Resembling  a  gland  or  aden.     A  gland-like  growth  in  the  naso-pharynx. 
Adipose.     Fatty.    Fat. 

Afferent.     Bearing  toward.     Afferent  vessels  enter  organs. 
Ala.     A  wing.     (Plural,  alee.) 
Alimentary.     Pertaining  to  food  or  aliment,  as,  the  alimentary  tract,  which  contains  the 

food  until  it  is  digested. 
Alkaline.     Opposite  of  acid.     An  alkali  turns  red  litmus  paper  blue. 
Alveolus.     The  border  of  the  jaw  bone,  named  for  the  cavities  which  contain  the  teeth. 

{Alveolus,  a  little  hollow.) 
Ameba.     A  one-celled,  jelly-like  living  being,  which  constantly  changes  its  form. 
Ameboid  movements.     Movements  which  cause  a  change  of  form,  like  those  of  the 

ameba. 
Amylopsin.     The  starch-digesting  ferment  of  pancreatic  fluid. 
Anastomosis.     The  opening  of  one  vessel  Into  another.     Literally — to  bring  to  a 

mouth. 
Ancon.     The  elbow.     Anconeus,  a  muscle  of  the  elbow-joint. 
Annulus.     .\  little  ring.     {Annulus  ovalis,  the  oval  little  ring  of  the  heart.) 
Anonyma.     Without  a  name. 

Antebrachium.     The  forearm.     From  ante,  before,  and  brachium,  the  arm. 
Antecubital.     Applied  to  the  space  in  front  of  the  elbow.     From  a7ite,  before,  and 

cubit,  the  forearm. 
Antnim.     A  cave.     The  hollow  in  the  maxilla  is  called  the  Antrum  of  Highmore. 
Aorta.     The  largest  artery  in  the  body. 
Apnea.     Suspension  of  breathing. 

Aponeurosis.     A  layer  of  strong  white  fibrous  tissue  (meaning  jrom  a  tendon). 
Aqueous.     Watery,  from  aqua,  water. 
Arachnoid.     Like  a  spider's  web,  for  fineness.     One  of  the  membranes  of  the  brain  and 

spinal  cord. 
Areolar.     Having  little  spaces. 

Artery.     .\  vessel  carrying  blood  away  from  the  heart. 
Arthrosis.     A  joint  or  articulation. 
Arytenoid.     Shaped  like  the  mouth  of  a  pitcher. 
Assimilation.     The  taking  up  of  nutriment  by  the  body  tissues,  in  such  a  manner  that 

it  becomes  a  part  of  them. 
Atlas.     A  fabled  giant  who  bore  the  globe  upon  his  shoulders.     The  first  cervical 

vertebra,  upon  which  the  skull  rests. 
Atrium.     A  hall,  a  chamber  of  the  heart  where  blood  enters. 
Atrophy.     Wasting.     From  a  Greek  word  signifying  wa«^  of  nourishment. 
Auricular.     Shaped  like,  or  belonging  to,  an  ear  or  auricle. 
Axis.     The  second  cervical  vertebra.     Named  because  of  the  pivot  around  which  the 

atlas  revolves  (like  a  wheel  around  an  axis). 
Axone.     .\n  axis.     The  essential  part  of  a  nerve  fiber. 

21  321 


322  GLOSSARY 

Azygos.     Without  a  yoke.     The  name  of  certain  vessels  which  are  not  in  pairs. 

Biceps.     Having  two  heads,  as  the  biceps  femoris;  biceps  brachii. 

Bicuspid.     Having  two  points  or  cusps.     A  bicuspid  tooth. 

Bone  corpuscle.     A  formation  cell  of  bone  tissue. 

Brachialis.     Belonging  to  the  arm,  or  brachium. 

Bronchus.    An  air  tube.   (Plural,  bronchi.)  The  smallest  air  tubes  are  called  bronchioles. 

Buccinator.     From  a  word  meaning  trumpet.     The  blowing  or  trumpeting  muscle. 

Bursa.     Literally,  a  purse.     The  bur  see  are  small  sacs  containing  fluid  and  found  in  the 

fascia  under  skin,  or  muscles,  or  tendons. 
Calcaneus.     The  heel  bone.     The  tendo  calcaneus,  or  tendo  Achillis,  is  attached  to  the 

calcaneus. 
Calculus.     A  stone-like  body  formed  in  some  fluid  of  the  body.    Renal  calculus,  in  the 

kidney;  biliary  c,  in  the  gall-bladder,  etc.  i 

Callus.     A  thickened  portion  of  the  skin.    The  material  thrown  out  (provisional  callus) 

for  the  repair  of  fractured  bone,  to  become  the  permanent  callus  when  the  bone 

is  completely  ossified. 
Cancellous,     Resembling  lattice  work.     A  cancellous  or  spongy  bone. 
Canine.     Resembling  a  dog.     Canine  teeth,  like  a  dog's  teeth. 
Canthus.     The  angle  at  the  meeting  of  upper  and  lower  eyelid;  plural  canthi. 
Capillary.     Resembling  a  hair  in  size.     {Capillus,  a  hair.) 
Capitellum,    or  capitulum.     A   little  head,  an  eminence  on  the  lower  extremity  of 

the  humerus. 
Capsule.     A  structure  which  encloses  an  organ  or  part.     (The  capsule  of  a  joint.) 
Carbo-hydrate.     A  substance  composed  of  carbon  and  water;  sugars  and  starches. 
Cardiac.     Belonging  to  the  heart  or  cardia. 
Caries.     Decay  of  bone.     Carious,  deca3dng. 
Carotid.    The  name  of  the  large  arteries  of  the  neck,  once  thought  to   cause  sleep. 

From  a  Greek  word  meaning  to  produce  sleep. 
Caruncle.    .A  small  soft  projecting  tumor.     Urethral  caruncle,  a  minute  tumor  of  the 

urethral  mucous  membrane,  made  up  mostly  of  nerves  and  vessels. 
Casein.     The  proteid  or  cheesy  part  of  milk. 
Cauda  equina.     A  horse-tail.     The  name  given  to  the  bundle  of  spinal  nerves  in  the 

lower  portion  of  the  spinal  canal. 
Cecum,     Blind.     The  blind  pouch  at  beginning  of  the  large  intestine. 
Celiac  (coeliac) .     Pertaining  to  the  celia  or  belly. 
Center.     In  the  nerve  system,  a  center  is  a  collection  of  gray  cells.     The  central  nerve 

system  comprises  the  brain  and  spinal  cord,  which  contain  the  large  nerve  centers. 

Central  convolutions  contain  a  majority  of  motor  centers. 
Cerumen.     The  wax  of  the  ear.     {Cera,  wax.) 
Cervix.     Neck.     Cervical,  belonging  to  or  resembling  a  neck. 
Choana.     A  funnel.     The  choancB  are  the  posterior  openings  from  the  nose  into  the 

pharynx. 
Choroid.     Like  the  chorioji,  which  is  a  fetal  membrane  bearing  blood-vessels. 
Cicatrix.     A  scar.     It  is  formed  of  fibrous  connective  tissue. 

Cilia.     Eyelashes.     Ciliated,  having  tiny  hair-like  projections,  as  ciliated  epithelium. 
Ciliary.     The  ciliary  region  of  the  eye  presents  radiating  lines,  caused  by  folds  of  the 

tissues  composing  it  {ciliary  processes) . 
Circumduction.     Leading  around.     This  is  the  motion  made  when  a  part  is  moved 

around  in  a  circle,  one  end  being  stationary.     The  extremities,  the  digits  and 

the  head,  may  be  circumducted. 
Circiunfiex.     To  bend  around.     Circumflex  arteries  wind  around  the  arm  or  thigh. 
Circumvallate.     Walled  around.     The  circumvallate  papillae  at  the  base  of  the  tongue 

are  encircled  by  a  ridge. 
Clavicle.     The  clavicula,  which  resembles  a  very  ancient  key.    ^ 

Climacteric.     Literally,  the  round  of  a  ladder.     Any  time  of  life  when  the  system  is  be- 
lieved to  undergo  marked  and  permanent  changes;  usually  applied  to  the  time 

of  the  cessation  of  menstruation. 
Coagulation.   From  coagulare,  to  curdle.  The  clotting  of  blood.  Coagulum,  a  blood  clot. 
Coccyx.     A  cuckoo's  beak.     The  bone  at  the  end  of  the  spinal  column,  named  from 

its  shape. 
Cochlea.     A  conch-shell.     A  cavity  of  the  internal  ear  resembling  a  snail-shell  in  form. 
Collateral    From  words  meaning  side  and  together.     Collateral  circulation  is  secured 

by  the  union  of  branches  of  two  vessels,  whereby  the  main  current  of  fluid  may 

be  carried  by  this  side  route  if  necessary. 


GLOSSARY  323 

Commissure.    A  placing  together.     A  commissure  connects  two  parts  of  an  organ,  as 

the  commissures  of  the  brain. 
Communis.     Common.     Applied  to  a  muscle  whose  tendons  are  common  to  several 

organs. 
Concha.     A  shell. 

Condyle.     A  knuckle.     A  rounded  eminence  of  bone. 
Conoid.     Shaped  like  a  cone. 
Convoluted.     Twisted. 
Co-ordinate.     From  words  meaning  together,  and  to  ordeKov  regulate.     Co-ordination 

is  the  systematic  acting  together  of  several  parts. 
Coracoid.     Like  a  crow's  beak.     The  coracoid  process  of  the  scapula. 
Corium.     Leather.     The  deep  portion  of  the  skin  from  which  leather  is  made. 
Cornea.     Horny.     The  tough  transparent  membrane  in  the  anterior  of  the  eyeball. 
Cornua.     Plural  of  cornu,  a  horn. 

Coronal  or  coronoid.     Pertaining  to,  or  resembling  a  crown. 
Coronary.     The  coronary  arteries  encircle  the  base  of  the  heart. 
Corpus  callosum.     The  transverse  commissure  of  the  cerebral  hemispheres. 
Corpuscle.     A  little  body.     A  blood  cell.     Malpighian  corpuscle,  a  structure  in  the 

kidney.    Lymph  corpuscle,  a  cell  formed  in  a  lymph  gland. 
Corpus   lutetun.     Yellow   body.     The  substance  formed   in  a   ruptured   Graafian 

follicle  of  the  ovary. 
Cortex.     Bark.     The  superficial  layer,  as  the  cortex  of  the  brain. 
Costal.     Relating  to  a  rib  or  casta. 

Coxae.     Plural  of  coxa,  the  hip;  os  coxa,  the  bone  of  the  hip. 
Cranium.     The  part  of  the  skull  which  contains  the  brain. 
Crest.     A  ridge  of  bone,  either  on  a  surface  or  at  the  border. 
Cretinism.     The  condition  of  a  cretin  or  undeveloped  person,  both  mentally  and 

physically. 
Cribriform.     Resembling  a  sieve. 

Cricoid.     Like  a  ring.     The  cricoid  cartilage  of  the  larynx  is  shaped  like  a  seal  ring. 
Crucial.     Like  a  cross.     The  crucial  ligaments  cross  each  other. 
Crural.     Belonging  to  or  like  the  lower  extremity,  from  crus,  a  leg;  as  the  crural  nerve, 

the  crura  (or  legs)  of  the  diaphragm. 
Cystic.     Relating  to  a  cyst,  or  a  sac  containing  fluid  {cystic  duct) .     A  cystic  ovary  has 

cysts  developed  from  its  substance. 
Deglutition.     The  act  of  swallowing. 
Deltoid.     Shaped  like  the  Greek  letter  delta,  J. 
Dental.     From  dens,  a  tooth,  belonging  to  a  tooth. 
Dentated.     Having  points  which  resemble  teeth. 
Dentition.     The  eruption  or  "cutting"  of  the  teeth. 
Diapedesis.     A  jumping  through.    The  passing  of  blood  cells  through  the  walls  of 

capillaries. 
Diaphragm.     A  wall  across  a  space.     The  muscle  which  separates  the  cavity  of  the 

thorax  from  that  of  the  abdomen. 
Diaphysis.     The  greater  part  of  the  shaft  of  a  bone. 
Diarthrosis.     A  movable  joint. 
Diastole.     A  Greek  word  meaning  a  drawing  apart.     The  dilation  of  the  chambers  of 

the  heart. 
Digit.     A  finger  or  toe. 
Distal.     Farthest  from  the  head  or  trunk. 
Dorsal.     Belonging  to  the  dorsum,  or  back. 

Duodenum.     Meaning  twelve.     The  duodenum  is  twelve  finger-widths  long. 
Dura  mater.     Hard  mother.     The  fibrous  outer  membrane  of  the  brain  and  spinal 

cord. 
Edema.     Swelling  caused  by  effusion  of  serous  fluid  into  areolar  tissues. 
Efferent.     Bearing  from.     Efferent  vessels  leave  organs. 

Effusion.     An  abnormal  pouring  out  (or  secreting)  and  collection  of  fluid  in  the  body. 
Eliminate.     From  worrls  meaning  without  the  threshold.     To  excrete  substances  which 

are  useless. 
Embryo.     The  ovum  and  structures  belonging  to  it  con'^titute  the  embryo,  until  the 

fourth  month  of  intrauterine  life. 
Endo-.     Within.     Endocardium,  within  the   heart.     Endothelium,  the    epithelium  of 

the  interior  of  circulatory  organs. 


324  GLOSSARY 

Endomysium,     The  sheath  of  a  muscle-fiber. 

Eridosteum.     The  lining  of  medullary  canals  in  long  bones. 

Ensiform.     Sword-shaped.     The  appendix  of  the  sternum. 

Enteric.     Pertaining  to  the  enteron  or  intestine,  as  enteric  or  typhoid  Jefuer. 

Enzyme.     Any  ferment  in  a  digestive  fluid. 

Epi.     Upon,  as  epi-condyle,  epidermis,  epiglottis. 

Epimysitmi.     The  connective  tissue  muscle  sheath. 

Epiphysis.     A  part  of  a  bone  which  is  formed  independently,  and  joined  later  to 

complete  the  whole  bone. 
Epithelial.     Pertaining  to  epithelium. 

Epithelium.     The  uppermost  or  superficial  layer  of  cells  of  a  body  surface. 
Erythrocyte.     A  red  cell  of  the  blood.     A  red  corpuscle. 
Esophagus.     From  a  Greek  word  meaning  to  carry  food.     The  esophagus  transmits 

food  from  pharynx  to  stomach. 
Ethmoid.     Sieve-like.     The  ethmoid  hone  has  many  openings  on  its  surface. 
Excretion.     A  waste  substance  to  be  removed  from  the  body.     The  process  of  removing 

waste  from  the  tissues. 
Extension.     Stretching  out  or  extending.     (Bending  backward  is  over-extension.) 
Eversion.     Turning  outward.     To  evert  an  eyelid  is  to  fold  it  back  so  as  to  expose  the 

interior  surface. 
Falx.     A  sickle. 
Falciform.     Sickle-shaped. 
Fascia.     A  band;  plural,  fascice.     The  tissue  which  binds  organs  or  parts  of  organs 

together. 
Fauces.     From  the  Latin  v^oxd.  faux,  the  throat.     Isthmus  of,  the  space  bounded  by 

the  soft-palate,  tonsils  and  tongue.     Pillars  of,  the    folds  connecting  the  soft 

palate  with  the  tongue  and  pharynx.     (The  tonsil  is  between  the  pillars  of 

either  side.) 
Femoral.     Belonging  to  the  femur  or  thigh  bone. 
Fetus.     After  the  fourth  month,  the  embryo  becomes  the  fetus. 
Fibrin.     A  proteid  substance  of  the  blood  which  causes  coagulation. 
Filiform.     Thread-like  in  shape,  slender;  as  filiform  papillse  of  the  tongue. 
Fimbria.     A  fringe;  fimbriated,  having  a  fringe-like  appearance. 
Fissure.     A  cleft  or  groove,  as  a  fissure  of  the  brain  surface. 
Fistula.     A  pipe.     A  tube-like  passage  caused  by  disease, 
Flava.     Plural  oi  flavus,  yellow.     Applied  to  elastic  ligaments  which  contain  yellow 

elastic  tissue. 
Flexion.     Bending.    Flexure,  a  bend. 

Follicle.     A  very  small  sac  (or  bag)  containing  a  secretion. 
Fontanelle.     A   little  spring.     A  membranous  spot  in  the  infant's  skull;  the  name 

suggested  by  the  rising  and  falling  caused  by  the  child's  respirations. 
Foramen.     A  hole.     Plural,  foramina. 
Fossa.     A  depression  or  concavity. 
Fourchette.     A  Httle  fork. 
Fovea.     A  small  pit.     The  fovea  centralis  is  a  tiny  depression  in  the  macula  lutea  of 

the  retina. 
Frentom.     A  curb  or  bridle.     The  frenum  linguce  is  the  fold  of  mucous  membrane 

.  attaching  the  tongue  to  the  floor  of  the  mouth. 
Fundus.     The  base. 

Fungiform.     Shaped  like  a  fungus  or  mushroom. 
Fusiform.     Spindle-shaped. 

Ganglion.     A  knot.     (Plural,  ganglia.)     A  collection  of  nerve  cells. 
Gaster.     The  stomach.     Gastric,  belonging  to  the  stomach  or  gaster. 
Gastrocnemius.     The  belly  of  the  leg.     The  prominent  muscle  of  the  calf  of  the  leg. 
Genioglossus.     Belonging  to  the  chin  and  tongue. 
Genu.     A  knee. 

Glabella.     A  little  smooth  space.     The  smooth  space  between  the  eyebrows. 
Gladiolus.     A  little  sword.     The  body  of  the  sternum. 
Gland.     A  collection  of  cells  which  can  form  a  secretion  or  an  excretion. 
Glans.     The  head  of  the  clitoris  or  penis. 

Glenoid.     Having  the  form  of  a  shallow  cavity.     Belonging  to  a  cavity. 
Glossopharyngeal.     Belonging  to  the  tongue  and  pharynx. 
Glottis.     The  upper  opening  of  the  larynx.     Epiglottis,  the  leaf-shaped  cartilage  upon 

the  upper  border  of  the  larynx. 


GLOSSARY  325 

Glucose.     Grape  sugar.     Dextrose. 

Gluteus.     Belonging  to  the  gluteus  or  buttock. 

Glycogen.     A  white  substance  formed  principally  in  the  liver.     Sometimes  called 

animal  starch. 
Gustatory.     Associated  with  the  sense  of  taste. 
Gyre.     From  gyrus,  a  circle.     A  convolution,  (referring  to  the  convolutions  of  the 

brain) . 
Haversian.     Name  applied  to  the  tiny  canals  in  bone  tissue,  from  the  English  anatomist 

Havers. 
Hepatic.     Belonging  to  the  liver  or  hepar. 
Hemoglobin.     The  oxygen-carrying  substance  of  red  blood  cells,  to  which  their  color 

is  due. 
Hemorrhoidal.     From  a  word  meaning  flowing  with  blood.     Pertaining  to  a  hemor- 
rhoid or  pile. 
Hiltun.     Literally,  a  little  thing.     Applied  to  the  depression  where  vessels  enter  and 

leave  an  organ. 
Hormones.     Chemical  substances  (character  unknown),  formed  (probablv)  in  ductless 

glands,  and  conveyed  by  the  blood  to  other  organs,  to  influence  their  activity. 
Hyaline.     Resembling  glass.     Hyaloid  has  a  similar  meaning. 
Hydration.     Saturating  with  water. 
Hydrocephalus.     A  collection  of  fluid  either  within  the  ventricles  or  outside  of  the 

brain. 
Hyoid.     U-shaped,  as  the  hyoid  bone. 
Hypertrophy.     Over-growth.     Derived  from  two   Greek  words  meaning  too   much 

nourishment. 
Hypochondrium.     Under    the   cartilage.     The   hypochondriac   region   is   under    the 

cartilages  of  ribs.     {Hypo-  under.) 
Hypogastric.     Under  the  stomach. 
Hypoglossal.     Under  the  tongue. 
Hypothenar.     Under  the  palm  or  sole.     The  eminence  on  the  medial  side  of  the  palm 

or  the  sole. 
Ileum.     A    roll    or    twist;    the    portion    of  small  intestine    which  appears  rolled  or 

convoluted. 
Ilium.     The  upper  portion  of  the  hip-bone  or  os  coxce. 
Incisor.     A  cutting  instrument.     The  front  teeth  are  incisors. 
Index.     Indicator.     The  first  finger  named  from  its  common  use. 
Infra.     Beneath. 

Infundibulom.     A  funnel-shaped  space  or  part. 
Inguinal.     Belonging  to  or  near  to  the  thigh  or  inguen. 
Inlet.     The  superior  opening  or  brim  or  strait  of  the  pelvis. 
Innominatvun.     Unnamed. 
Inorganic.     A    term    applied   to  certain  substances,  mostly  mineral,  found  in  all 

organs  but  not  produced  by  them. 
Instep.     The  bend  of  the  foot,  dorsal  aspect. 

Inter.  Between,  as  intercostal,  between  ribs;  intercellular,  between  cells,  etc. 
Inversion.  A  turning  in,  as  inversion  of  the  eyelashes;  inversion  of  the  foot. 
Invertin.     The  ferment  of  intestinal  juice. 

Involution.     The  changing  back  to  a  former  condition,  of  an  organ  which  has  ful- 
filled a  function,  as  the  involution  of  the  uterus  after  parturition. 
Iris.     A  circle  or  halo  of  colors.     The  colored  circle  behind  the  cornea  of  the  eye. 
Ischium.     The  lowest  part  of  the  hip-bone  or  05  coxcb. 

Jejunum.     Empty.     The  third  portion  of  the  small  intestine,  usually  found  empty. 
Jugular.     Belonging  to  the  neck  or  jugulum. 
Kidney  or  ren  (plural,  renes).     An  important  organ  of  elimination  or  excretion,  in 

which  the  urine  is  formed. 
Labium.     A  lip.     (Plural,  labia.) 

Lacrimal.     Having  to  do  with  tears  or  lacrymce,  as  the  lacrimal  gland. 
Lacteal.     Like  milk  (from  lac,  milk).     The  lacteals  are  lymph- vessels  which  carry  the 

milky-looking  chyle 
Lactose.     Milk  sugar. 

Lambdoid.     Resembling  the  Grepk  letter  lambda,  X. 
Lamella.     A  little  plate,  or  thin  layer. 
Lamina.     A  plate  or  layer. 


326  GLOSSARY 

Larynx.     The  part  of  the  air-passage  extending  from  the  base  of  the  tongue  to  the 

trachea. 
Latissimus.     Broadest.    Latissimus  dorsi,  broadest  of  the  back. 
Lens.     A  glass  or  crystal  curved  and  shaped  to  change  the  direction  of  (or  refract) 

rays  of  light. 
Lentifonn.     Shaped  like  a  lens. 
Leptomeningitis.     Inflammation  of  the  thin  membranes  of  the  brain — the  arachnoid 

and  pia  mater. 
Leucocyte.     A  white  cell  of  the  blood  or  lymph.    Leucocytosis,  an  increase  in  the  num- 
ber of  leucocytes. 
Levator.     A  lifter.    Levator  palpebrm,  lifter  of  the  eyelid, 
Linea.     A  line. 
Linea  alba.     A  white  line. 
Linea  aspera.     A  rough  line. 
Lingual.     Belonging  to  the  tongue  or  lingua. 
Lobule.     A  little  lobe. 
Lumbar.     Belonging  to  the  loin  or  lumbus. 
Macula.     A  spot.     Macula  lutea,  yellow  spot. 
Major.     Greater  or  larger. 
Malar.     Belonging  to  the  cheek  or  mala. 
Malleolus.     A  little  hammer.     The  two  malleoli  are  the  lower  extremities  of  tibia 

and  fibula. 
Mammary.     Pertaining  to  the  breast  or  mamma. 
Mandible.     Derived  from  mandere,  to  chew.     The  lower  jaw-bone. 
Manubrium.     A  handle.     The  first  part  of  the  sternum. 
Masseter.     A  chewer.     One  of  the  muscles  of  mastication  or  chewing. 
Mastitis.     Inflammation  of  the  breast. 
Mastoid.     Shaped  like  a  breast. 

Maxilla.     The  jaw-bone.     Applied  to  the  upper  jaw-bone. 
Meatus.     A  passage. 
Medial.     Toward  the  middle  line. 
Median.     Middle,  as  the  median  line  of  the  body. 
Mediastinum.     From  Latin  words  meaning  to  stand  in  the  midst.     The  space  in  the 

middle  of  the  thorax. 
Medulla.     Marrow. 

Medullary.     Pertaining  to,  or  like,  marrow.     The  medullary  canals  contain  marrow 
Meninges.     Membranes.     Membranes  of  the  brain  and  spinal  cord. 
Mental.     From  the  Latin  word  mens,  the  mind. 
Mental.     From  the  Latin  word  mentum,  the  chin. 
Mesentery.     From  two  Greek  words,  meaning  middle  and  bowel.     (The  mesentery 

connects  the  bowel  with  the  posterior  abdominal  wall.) 
Metastasis.     From  a  Greek  word  meaning  to  transpose.  ,         - 

Minimus.     Least  or  smallest.     Minimi  digiti,  of  the  smallest  digit. 
Minor.     Lesser. 

MitraL     Resembling  a  miter  in  outline. 

Molar.     Like  a  mill-stone  or  mola.     The  molar  teeth  grind  the  food. 
Mucous.     Containing  or  resembling  mucus. 

Mucus.     A  thick  clear  fluid  secreted  by  the  cells  of  mucous  membranes, 
Naris.     The  nostril.     (Plural,  nares.) 
Navicular.     Boat-shaped,  as  the  navicular  bone. 

NecrosiSo     The  death  of  a  portion  of  tissue,  while  still  surrounded  by  living  structures. 
Neural.     Pertaining  to  nerves.     The  neural  axis  is  the  spinal  cord.     The  Pleural  canal 

is  the  spinal  canal.     The  neural' cavity  contains  the  brain  and  spinal  cord. 
Neuron.     A  single  nerve  cell  with  its  branches. 
Nucha.     The  nape  of  the  neck. 

Nucleolus.     A  smaller  nucleus  within  the  nucleus  of  a  cell. 
Nucleus.     A  smaU  round  body  near  the  center  of  a  cell.     The  most  important  part  of  . 

a  nucleated  cell. 
Nutrient.     Nourishing. 

NutritioUr    The  process  of  nourishing  the  cells  of  living  tissues. 
Olecranon.     The  large  process  at  the  upper  end  of  the  ulna.     The  head  of  the  elbow. 
Occipital.     Belonging  to  the  back  of  the  head,  or  the  occiput. 
Odontoid.     Resembling  a  tooth  in  shape. 


GLOSSARY  327 

Omentum.     A  fold  of  peritoneum  connected  with  the  stomach. 

Omos.     The  shoulder.     Omo-hyoid,   belonging  to  shoulder  and  hyoid  bone,  as  the 

omo-hyoid  muscle. 
Ophthalmic.     Belonging  to  the  eye  or  ophthalmos. 
Ora  serrata.     The  serrated  or  toothed  margin  of  the  retina. 
Orbicular.     Ring-shaped.     A  ligament  which  resembles  a  little  circle. 
Organ.     A  structure  designed  for  a  particular  function  or  use.     Organic  substances 

are  formed  in,  or  by,  organs. 
Os.     A  bone.     (Plural,  ossa.) 
Os.     A  mouth.     (Plural,  ora.) 
Osseous.     Bony. 

Ossification.     The  formation  of  bone. 
OsTeology.     The  science  which  treats  of  bones. 

Ostivmi  venostmi.     A  venous  door.     The  door  or  opening  from  an  atrium  to  a  ven- 
tricle in  the  heart,  for  the  passage  of  venous  blood. 
Outlet.     The  inferior  opening  or  strait,  of  the  pelvis. 
Ovum.     An  egg.     (Plural,  ova) 

Palpebra.     An  eyelid.     Palpebral  fissure,  the  fissure  between  the  eyelids. 
Pancreas.     From  words  meaning  all  and  flesh.     Pancreatic  fluid  digests  all  foods. 
Papilla.     A  Latin  word  meaning  a  nipple.     A  soft  conic  eminence. 
Parietal.     Resembling  a  wall  (paries). 

Parotid.     Near  the  ear.     The  parotid  gland  is  around  the  external  ear. 
Parturition.     The  act  of  bringing  forth,  or  giving  birth  to,  young. 
Patella.     A  little  pan.     The  sesamoid  bone  in  front  of  the  knee-joint;  the  "  knee  pan." 
Pectoral.     Connected  with  the  breast,  as  pectoral  muscles. 
Pedicle.     A  little  foot. 

Pelvis.     A  basin.     The  cavity  in  the  lowest  part  of  the  trunk. 
Pericardium.     Around  the  heart. 
Perichondrium.     Around  cartilage. 

Perimysium.     The  connective  tissue  around  small  bundles  of  muscle  fibers. 
Perineal.     Pertaining  to  the  perineum,  that  region  of  the  body  in  front  of  the  anus. 
Periosteum.     Around  bone. 
Peristalsis.     From  two  Greek  words,  meaning  around  and  constriction.     The  intestinal 

movements  which  propel  the  food. 
Peritoneum.     From  two  Greek  words,  meaning  around  and  to  stretch.     The  serous 

membrane  around  abdominal  organs. 
Peroneal.     Relating  to  the  fibula  or  per  one.    Peroneal  nerves  supply  muscles  on  the 

fibula. 
Petrous.     Hard,  like  a  rock. 
Phagocyte.     White  blood-cells  having  the  power  to  take  micro-organisms  into  their 

substance  and  to  digest  them. 
Phalanges.     Plural  of  phalanx,  a  body  of  troops  drawn  up  closely  together.     The 

fingers  and  toes. 
Pharynx.     That  part  of  the  food  passage  which  connects  the  mouth  and  esophagus. 

The  upper  part  is  the  naso-pharynx,  an  air  passage. 
Phlebotomy.     Cutting  a  vein.     The  operation  of  bleeding  or  venesection. 
Pia  mater.     Tender  mother.     The  delicate  membrane  which  bears  the  blood-vessels 

of  brain  and  cord. 
Pigment.     Coloring  matter. 

Plantar.     Belonging  to  the  sole  of  the  foot  or  planta. 
Plasma.     Something  moulded.     The  name  given  to  the  fluid  portion  of  the  blood,  from 

which  tissues  are  formed. 
Platysma.     Broad.     Platysma  muscle. 
Pleura.     A  side.     The  name  of  the  serous  membrane  which  lines  the  thorax  and  covers 

the  lungs. 
Plexus.     An  arrangement  of  vessels  and  nerves  which  appear  to  be  woven  together. 
Pneumogastric.     Belonging  to  the  lungs  and  stomach. 
Pollicis.     Genitive  form  of  pollex,  the  thumb. 
Polymorphonuclear.     Having  nuclei  of  various  shapes. 
Poples.     The  ham;  a  S7)ace  behind  the  knee  (popliteal  spcce). 
Popliteal.     Belonging  to  the  poples  or  back  of  the  knee. 
Porta.     A  gate.     The  portal  vein  enters  the  porta  or  gate  of  the  liver. 
Prehension.    Taking  hold  of. 


328  GLOSSARY 

Pre-molar.     Applied  to  the  teeth  which  stand  immediately  in  front  of  the  molars. 

Process.     In  anatomy,  a  projection. 

Pronation.     Literally,  bending  forward.     The  position  of  the  hand  when  the  thumb  is 

toward  the  body.     The  act  of  turning  the  hand  face  downward,  or  in  the  prone 

position. 
Prostate.     From  Greek  words  meaning  to  stand  before.     The  prostate  gland  is  in  front 

of  the  neck  of  the  bladder. 
Protoplasm.     A  simple  gelatinous  cell  substance.     Bioplasm, 
Protuberance.     A  knob-like  projection, 
Proximal.     Near  the  head  or  trunk. 
Psychical.     Pertaining  to  the  mind. 
Pterygoid.     Wing-shaped. 
Pubes.     The  anterior  portion  of  the  os  coxae. 
Pulmonary.     Pertaining  to  the  lung  or  pulmo. 
Quadriceps.     Four  headed. 
Rachitis.     From  two  words  meaning  spinal  column  and  inflammation.     A  disease  in 

which  the  bones  are  deficient  in  lime  salts. 
Radius.     A  rod  or  spoke.     The  lateral  bone  of  the  forearm. 
Ramus.     A  branch,  as  the.  ramus  of  the  mandible. 
Raphe.     A  seam.     The  union  of  two  parts  in  a  line,  like  a  seam. 
Reaction.     Response  to  a  stimulus  or  test.     The  iris  reacts  to  the  stimulus  of  light. 

Urine  reacts  to  the  litmus  test. 
Reflex  action.     The  simplest  form  of  nerve  response. 

Receptaculum  chyli.     Receptacle  of  the  chyle,  the  beginning  of  the  thoracic  duct. 
Recession.     Withdrawal,  as  the  margin  of  the  gums  from  the  teeth. 
Rectus.     Straight,  as  rectus  muscles.     Rectum  has  the  same  meaning. 
Recurrent.     Running  back.     Recurrent  arteries  turn  back. 
Renal.     Pertaining  to  the  ren  or  kidney. 
Retina.     A  net.     The  complicated  nerve  coat  of  the  eye. 
Rugae.     Folds.     (Plural  of  ruga").     Wrinkles. 
Saccharose.     Cane  sugar. 
Sacral.     Relating  to  the  sacrum,  or  bone  which  protects  the  pelvic  organs  which  were 

held  sacred  by  the  ancients. 
Sagittal.     Like  an  arrow — straight.     The  straight  suture  of  the  skull. 
Saline.     Salty. 

Saliva.     The  mixed  secretions  of  glands  of  the  mouth  and  salivary  glands. 
Saphenous."    Manifest  or  plainly  seen.     The  large  superficial  vein  on  the  medial 

side  of  the  lower  extremity  and  the  longest  vein  in  the  body. 
Sartorius.     From  the  Latin  5a?'ior,  tailor.     The  "  tailor  muscle." 
Sciatic.     Ischiatic.     Pertaining  to  the  ischium. 

Sclerotic.     Hard.     The  sclerotic  is  the  tough  fibrous  coat  of  the  eye;  the  sclera. 
Scrobiculus  cordis.     Literally,  pit  of  the  heart.     The  little  depression  at  the  end  of 

the  sternum.     The  "pit  of  the  stomach." 
Sebaceous.     Applied  to  the  glands  which  produce  the  oil  or  sebum  of  the  skin. 
Secretion.     A  substance  either  nourishing  or  useful,  formed  by  glandular  cells. 
Septtun.     A  partition.     (Plural,  septa.) 

Serous.     Of  the  nature  of  serum,  a  thin  watery  fluid  derived  from  the  blood. 
Serrated.     Having  teeth  like  the  border  of  a  saw. 
Serum.     A  watery  fluid  separated  from  blood. 

Sesamoid.     Resembling  a  grain  in  form.     Applied  to  small  nodules  of  bone  some- 
times found  in  tendons. 
Shaft.     The  main  portion  of  a  long  bone. 
Sigmoid.     Curved    like    the    letter  S.     As  the  sigmoid   (or  transverse)    sinus;   the 

sigmoid  colon. 
Sinus.     A  curve,  or  a  hollow.     A  bone  sinus  contains  air.     An  abnormal  passage 

opening  on  the  surface  of  the  body  is  sometimes  called  a  sinus. 
Soluble.     That  which  can  be  dissolved  or  made  into  a  solution. 
Sphenoid.     Wedge-shaped. 
Sphincter.     A  muscle  which  closes  an  orifice. 
Splanchnic.     Pertaining  to  the  viscera  or  internal  organs. 
Squamous.     Shaped  like  a  scale. 
Steapsin.     The  pancreatic  ferment  which  digests  fats. 
Stemtun.     Breast  bone. 


GLOSSARY  329 

Striated.     Striped 

Styloid.     Pointed,  like  the  stylus,  which  was  used  in  ancient  times  for  writing. 

Sub.     Under. 

Subcutaneous.     Under  the  skin. 

Submucous.     Under  mucous  membrane. 

Subserous.     Under  serous  membrane. 

Sudoriferous.  Bearing  sweat,  as  sudoriferous  glands.  {Sudoriparous  has  the  same 
meaning.) 

Super.     Above. 

Superciliary.     Above  the  eyelashes. 

Supercilium.     The  eyebrow,  or  prominence  above  the  eyelashes. 

Supination.  The  attitude  of  one  lying  on  the  back.  The  position  of  the  hand  when 
the  little  finger  is  next  to  the  body,  or  when  lying  upon  the  back. 

Supra.     Above. 

Sural.     Belonging  to  the  calf  or  sura,  as  the  sural  muscles. 

Surgical  neck.  The  constriction  below  the  head  of  a  long  bone  at  the  narrowest 
portion  of  the  shaft.  The  anatomic  neck  is  the  constriction  (however  slight) 
immediately  next  to  the  head,  between  it  and  the  shaft.  The  surgical  neck 
of  the  humerus  and  the  anatomic  neck  of  the  femur  are  best  examples. 

Suture.     A  seam.     (Latin,  stdiira).     The  joints  of  the  cranium  are  sutures. 

Symphysis.     A  growing  together,  as  the  symphysis  of  the  mandible. 

Synarthrosis.     An  immovable  joint. 

Synovia.  A  fluid  resembling  the  white  of  an  egg,  found  in  joint  cavities  and  vaginal 
synovial  membranes. 

Systole,  A  Greek  word  meaning  contraction.  The  contraction  of  the  chambers  of 
the  heart. 

Talus.     The  ankle  bone  upon  which  the  tibia  rests. 

Tendo  Achillis.  The  tendon  of  Achilles.  The  tendon  of  calf  muscles  attached  to 
the  calcaneus  or  heel  bone  by  which  Achilles  was  held  when  his  mother  sub- 
merged him  in  the  river  Styx,  to  render  him  invulnerable.  Only  the  heel 
remained  un-wetted. 

Tentorium.  A  tent.  The  tentorium  cerebelli  (of  the  cerebellum)  covers  the  cere- 
bellum. 

Teres.     Round.     (Ligamentuni  teres — round  ligament.) 

Testes,  or  Testicles.     The  glandular  bodies  which  secrete  semen. 

Thalamus.  A  Greek  word  meaning  a  bed.  The  optic  thalamus  is  in  the  base  or 
bed  of  the  brain. 

Thenar.  Relating  to  the  palm  or  sole.  Hypothenar — under  the  palm  or  sole — applied 
to  the  eminences  on  the  side  corresponding  to  the  little  finger  or  toe. 

Thorax.     The  chest.     The  portion  of  the  trunk  which  contains  the  heart  and  lungs. 

Thyroid  or  thyreoid.     Shield  shaped. 

Torticollis.     Twisted  neck,  wry  neck. 

Trabeculae.  Little  beams.  (Plural  of  trdbecula.)  The  cross  bands  of  connective 
tissue  which  support  soft  structures — as  in  the  spleen. 

Trapezium.  A  four  sided  symmetrical  figure.  Trapezoid,  resembling  a  trapezium, 
but  not  symmetrical.     Trapezius,  applied  to  a  muscle  of  the  back. 

Triceps.     Three  headed. 

Trigone.     A  space  or  surface  having  three  angles  or  corners. 

Trochanter.  From  a  word  signifying  a  wheel.  (The  muscles  which  are  attached 
to  the  trochanters  roll  the  femurs.) 

Trochlea.  A  pulley.  A  trochlear  surface  is  a  grooved  convexity,  as  the  trochlea  of 
the  humerus. 

Trypsin.     The  ferment  of  the  pancreas  which  digests  proteids. 

Tuber.     A  swelling  or  bump. 

Tubercle.     A  small  projection  like  a  swelling. 

Tuberosity.     A  large  projection  on  a  bone. 

Tumor.     A  swelling  of  soft  tissues. 

Turbinated.     Rolled,  like  a  scroll. 

Tympany.  The  condition  caused  by  inflation  of  intestines  with  gas,  so  that  they 
sound  hollow  upon  percussion,  like  a  tympanum  or  drum. 

Ulna.     A  cubit;  the  elh>ow.     The  longer  bone  in  the  medial  side  of  the  forearm. 

Umbilicus.  From  a  Latin  word,  umbo,  the  name  of  the  elevated  or  depressed  point 
in  the  middle  of  an  oval  shield. 


330  GLOSSARY 

Ungual.     Belonging  to  the  nail  or  unguis. 

Urea.     A  substance  representing  the  chief  nitrogenous  product  of  tissue  waste. 

Ureter,     The  duct  of  the  kidney,  which  conveys  urine  to  the  bladder. 

Urethra.     The  passage  through  which  urine  is  expelled  from  the  bladder. 

Uvula.     From  uva,  a  grape,  or  cluster  of  grapes  (which  hangs  down  from  the  branch 

where  it  grows. 
Vaginal.     Like  a  sheath. 

Vallate.     Situated  in  a  cavity  which  is  surrounded  by  a  ridge. 
Valvulae  conniventes.     Little  valve-like  folds.     Seen  on  the  mucous  coat  of  the  small 

intestine. 
Vascular.     Having  many  blood-vessels. 

Vaso-motor.     Literally,  vessel-mover.     Applied  to    the  nerves  which  dilate  blood- 
vessels or  contract  them. 
Velum.     Veil.     Velum  palati,  the  veil,  or  soft  hanging  portion  of  the  palate  or  roof 

of  the  mouth. 
Vena  cava.     A  large  hollow  vein. 

Venesection.     Cutting  a  vein.     "Bleeding"  or  phlebotomy. 
Ventral.     Toward  the  front  of  the  body,  as  the  ventral  cavity. 
Ventricle.     Literally,  a   little  belly.    Fom  the  Latin  venter.     A  cavity  in  the  brain, 

or  in  the  heart. 
Vermiform.     Worm-shaped. 
Vertebra.     From  a  Latin  word  meaning  to  turn.     Certain  movements  of  the  vertebrae 

turn  the  body  from  side  to  side. 
Vertex.     The  crown  of  the  head. 
Vestibule.     A  cavity  of  the  internal  ear  through  which  stimulating  impulses  are 

transmitted  to  auditory  and  vestibular  nerves. 
Villus.     A  hair  (pi.  villi) .     The  villi  of  the  intestine  are  hair-like  in  shape  and  belong 

to  the  mucous  coat. 
Viscus.     An  internal  organ  of  the  head  or  trunk.     (Plural,  viscera.) 
Vitreous.     Glassy.     The    vitreous    humor    resembles    glass    in    appearance.     The 

vitreous  layers  of  the  skull  are  brittle  like  glass. 
Volar.     Belonging  to  the  palm  or  vola. 
Xyphoid.     Sword-shaped.     The  third  piece  of  the  sternum  is  the  xyphoid  or  ensiform 

appendix. 
Zygoma.     A  yoke.     The  arch  of  bone  at  the  side  of  the  face  formed  by  zygomatic 

processes  of  frontal  and  maxillary  bones. 


INDEX. 


Abdomen,  abdominal  organs,  297 

regions  of,  2y8 
Abdominal  brain  (Solar  Plexus)    264 
Abdominal  wall,  88 
Absorption,  14S,  151 
Accommodation,  278 
Acromegaly,  224 
Adipose  tissue,  3 
Adrenal  bodies,  222 
Air,  or  atmosphere,  143,  202 
Alimentary  canal,  120 
Ameboid  movements,  153 
Anatomic  position  and  use  of  terms,  i 
.\nimal  heat,  226 
Antibrachium  or  forearm,  52 
Antrum  of  Highmore,  2 1 
Aorta,  167  169 
Apnea,  209 

Aponeurosis,  description  of,  79 
Apophysis,  12 
Apparatus,  6 

Appendbc  ceci  (vermiformis) ,  134 
Aqueduct  of  Sylvius  (of  cerebrum),  253 
Aqueous  humor,  279 
Arachnoid  of  brain,  255 

of  cord,  232 
Arbor  vitae,  252,  (illus.  251) 
Arches  of  foot,  68 

of  hand,  172,  173 

of  vertebrae,  35 
Areolar  tissue,  3 
Arm,  bone  of,  52 

muscles  of,  96 
Arterioles  and  arttvies,  156 
Articular  surface,  10 
Articulations  or  joints,  14 

of  cranium,  20 

of  face,  24 

of  lower  extremity,  63 

of  pelvis,  46 

of  spinal  column,  38 

of  thorax,  43 

of  upper  extremity,  56 
Ascites,  6 
Asphyxia,  209 
Assimilation,  151 
Atlas,  36 

Auditory  tube  (Eustachian),  125,  273 
Auricle  of  heart,  158 
Axillary  space,  300 
Axis  (artery),  171 

(bone),  36 
Axon,  229 

Bifurcation  of  aorta,  178 
Bile.  139,  147 


Bladder,  283 
Bioplasm,  2 
Blood,  152 
Bone,  articular,  14 

markings,  10 

repair  of,  72 

tissue,  8 
Bones,  completion  of,  70 

in  infancy,  71 

of  abdomen,  44 

of  cranium,  16 

of  ear,  275 

of  face,  20 

of  lower  extremity,  59 

of  neck,  31 

of  pelvis,  44 

of  spinal  column,  35 

of  thorax,  40 

of  upper  extremity,  50 

shapes  of,  11 
Brain,  249 

fissures  of,  251,  252 

hemispheres  of,  2  50 

lobes  of,  251 
Breast  (mammarj'  gland),  219 

muscles  of,  96 
Bronchi,  204 
Bronchial  muscle,  205 
Bursa  (pleiiral,  bursa),  67,  77 

Callus,  72 

Canal,  adductor,  302 

anal,  136 

auditory,  273 

carotid,  19 

central  (of  cord),  232 

femoral,  303 

Haversian,  9 

Hunter's  (or  adductor),  302 

inguinal,  303 

internal  auditory,  19,  273 

medullary,  9 

nasal  (or  lacrimal),  30 

neural,  39 

nutrient,  70 

semicircular,  274 

spinal  (neural  or  dorsal),  49 
Cancellous  or  spongy  tissue,  9 
Capillaries,  156 
Capitulum  (capitellum) ,  52 
Capsule,  Bowman's,  212 

internal,  251 

of  joints,  14 

of  lens,  278 

of  Tenon,  279 
Cardiac  impulse,  196 


331 


2>2,- 


INDEX 


Cartilage,  4 

articular,  14 

costal,  41 

fibro-,  semilunar,  65 
sterno-clavic,  56 
triangular,  57 
Cauda  equina,  235 
Cavities  of  body,  48 

dorsal  or  neural,  49 

ventral  or  visceral,  49 
Cecum,  134 
Cell,  description,  2 
Cell  body  (nerve),  229 
Centers,  brain  (illus.),  260,  261 

nerve,  231 

of  ossification,  11 
Central  fissure,  251 
Cerebellum,  252 
Cerebral  localization,  260 
Cerebro-spinal  fluid,  233 

system,  230 
Cerebrum,  250 
Cervical  nerves,  236 
Cervix  uteri,  285,  286 
Chambers  of  eye,  279 
Choroid  coat  of  eye,  276 
Chyle,  147 
Chyme,  144 
Cilia,  of  air  passages,  205 

of  eyelids,  217 
Ciliary  muscle,  278 
Circulation,  (def.),  151 

collateral,  176,  181 

fetal,  189 

portal,  189 

pulmonary,  167 

systemic,  167,  168 
Circumcision,  291 
Clitoris,  289 

Coagulation  of  blood,  155 
Coccyx,  38 
Cochlea,  274 
Colon,  135 
Colostrum,  220 
Compact  bone  tissue,  9 
Compression  of  arteries,  310 
Condyle  (def.),  10 
Condyles,  occipital,  17 

of  femur,  60 

of  mandible,  23 

of  tibia,  61 
Conjoined  tendon,  90,  298 
■  Conjunctiva,  276 
Connective  tissue,  75 
Corium  of  skin  (cutis  vera),  214 
Cornea,  276 
Corpus  callosum,  251 
Corpuscle  of  blood,  152,  153 

of  kidney  (Malpighian),  212 

of  skin  (touch),  214 

of  spleen,  221 
Corpus  leutum,  288 
Cortex  of  brain,  249 


Cranium,  16,  25 
Crest  (def.),  10 
Crura  of  cerebrum,  253,  267 

of  diaphragm,  91 
Crystalline  lens,  278 
Cutis  vera  (skin),  214 

Dartos,  290 

Defecation,  148 

Deglutition,  144 

Dendrite,  229 

Dentition  (eruption  of  teeth),  32 

Diameters  of  pelvis,  48 

Diapedesis,  154 

Diaphragm,  91,  113 

of  pelvis,  103 
Diaphysis,  12 
Diastole  of  heart,  161 
Digestion,  144,  151 
Digestive  fluids,  121 
Dorsal  cavity,  48 
Duct,  common  bile,  139 

cystic,  139 

hepatic,  139 

lacrimal,  279,  280 

pancreatic,  13S 

right  lymphatic,  197 

Stenson's,  124 

thoracic,  197 

Wharton's,  124 
Ductus  arteriosus,  igo 

communis  choledochus   (or  common 
bile  duct),  139 

deferens  (vas  def.),  291 
Duodenum,  132 
Dura  mater,  brain,  255 

cord,  233 
Dyspnea,  209 

Ear,  273 
Edema,  196 
Elastic  tissue,  3 
Elimination,  organs  of,  226 
Endocardium,  160 
Endosteum,  10 
Endothelium,  6,  156 
Enzyme  (def.),  121 
Epicardium,  164 
Epicondyle  of  femur,  60 

of  humerus,  52 
Epidermis,  214 
Epigottis,  204 
Epiphysis,  12 
Epithelium,  4 

ciliated,  5,  205 

respiratory,  208 
Erythrocyte  (red  cell),  152 
Esophagus,  126 
Ethmoid  notch,  17 
Eustachian  tube  (auditory),  125,  273 
Excreting  organs,  6,  226 
Excretion,  226 
Expiration,  act  of,  208 


INDEX 


333 


External  genital  organs,  289 
Extremities  compared,  304 
Eye,  276 
Eyebrows,  279 
Eyelids,  279 

Face,  bones  of,  20,  27 

muscles  of,  84 

vessels  and  nerves,  292 
Fallopian  or  uterine  tubes,  286 
Fabc  cerebri,  255 
Fascia  of  body,  deep,  75 

iliac,  103 

lata,  76 

lumbar,  77 

palmar,  102 

pelvic,  103 

plantar,  in 

superficial,  77 

temporal,  84-292 

transversalis,  93 

transverse  of  leg,  307 
Feces,  147 
Fibrin,  155 
Fibrous  tissue,  3 
Fissure  of  Rolando  (central),  251 

of  Sylvius,  251 

transverse  of  liver  (porta),  139 
Floor  of  mouth,  121 

of  pelvis,  103 

of  thorax,  91 
Fontanelles,  28 
Foods,  141 
Foramen  (def.),  10 

infraorbital,  21 

intervertebral,  40 

jugular,  26 

magnum,  17 

mental,  23 

Munro,  253 

obturator  or  thyroid,  46 

optic,  30 

ovale,  190 

sciatic,  47 

supraorbital,  17 

transverse,  36 

vertebral,  36 
Forearm,  bones  of,  52 

muscles  of,  98 
Foreskin  (prepuce),  291 
Fossa  (def.),  10 

glenoid,  51 

interconriyloid,  60 

ischio-rectal,  300 

lacrimal,  17 
'       navicularis,  289 

ovale  (heart),  158 
(thigh),  77 

subscapular,  51 
Fossae  of  skull,  28 
Frenum  lingua:  (bridle  of  tongue),  122 

Gall  bladder,  139 


Ganglia,  basal,  251 

semilunar,  264 

sympathetic  (autonomic),  263-5 
Ganglion,  231 

Gasserian,  257 

root  of  spinal  nerve,  233 
Gastric  juice,  128 
Glabella,  17 
Gland  (definition),  5 

of  Bartholin,  290 

ceruminous,  273 

ductless,  220 

intestinal,  131,  133,  134 

Peyer's,  134 

lacrimal,  280 

lymph,  196 

mammary,  219 

Meibomian  (tarsal),  280 

prostate,  284 

salivary,  124 

sebaceous,  216 

sudoriferous,  216 

tissue,  5 
Glossary,  321 
Glottis,  282 
Graafian  follicle,  287 
Greenstick  fracture,  72 
Glycogen,  149 

Hair,  217 

Hamstring  tendons,  108 

Heart,  157 

diastole  of,  161 

function  of  chambers,  161 

muscle,  158 

sounds,  163 

systole  of,  161 

tendinous  cords  of,  160 
Hearing,  273-5 
Heat  (body),  226 
Hemoglobin,  153 
Hemorrhoidal  arteries,  180 
Hernia,  304 

retro-peritoneal,  300 
Hip-bone  (os  coxrc),  44 
Housemaid's  knee,  67,  77 
Hvmen,  289 
Hypophysis  cerebri,  224 
Hyperpnea,  209 

Ileum,  133 
Ilium  (os),  44 
Inguinal  rings,  298,  303 
Inorganic  substances  of  bone,  8 
Insertion  of  muscles,  79 
Inspiration,  act  of,  20S 
Instep  (arches  of  foot),  68 
Intercellular  substance,  3 
Intermuscular  septa,  76 
Interosseous  sjjaces,  53,  55,  61,  63 
Internal  secretions,  220 
Intestine,  130 
large,  134 


334 


INDEX 


Intestine,  small,  131 
Iris,  277 

Joint  or  articulation,  14 

immovable,  14 

motions  of,  15 

movable,  14 

yielding,  15 
Jugular  notch,  40 

veins,  184 

Kidneys,  211 

Labia  majora,  289 

minora,  289 
Labyrinth  (ear),  274 
Lacteals,  150 
Lanugo,  217 

Large  vessels  and  nerves,  309 
Larynx,  204 
Leucocytes,  153 
Leukemia,  221 
Ligament,  annular,  loi,  in 

of  Bigelow  (Y),  ileo-femoral,  65 

broad,  289-90 

crucial,  66 

deltoid,  67 

dorsal  of  wrist,  102 

elastic,  38,  68 

Gimbernat's,  303 

inguinal  (Poupart),  47,  76,  90,  298 

of  liver,  140 

orbicular,  58 

of  patella,  105 

sacro-sciatic,  46 

structure  of,  14 

suspensory  of  lens,  278 

transverse  of  ankle,  67 
Ligaments  of  uterus,  288 
Ligamentum  nuchae,  39 

teres,  63,  64 
Linea  alba,  90 

aspera,  60 

semilunaris,  89 
Lineffi  transversae,  91 
Liver,  139 

Lumbo-sacral  cord,  242 
Lungs,  205 
Lymph,  150,  195 

capillaries,  194 

corpuscles,  196 

nodes  (lymphatic  glands),  196 

origin  of,  195 

spaces,  194 

vessels,  194 
Lymphatic  ducts,  197 

system,  194 
Lymphocytes,  196 

Malleolus,  lateral,  61 

medial,  61 
Manubrium,  40 
Marrow,  9 


Mastication,  145 

Meatus,  external  auditory,  273 

of  nose,  202 

of  urethra,  283 
Median  line,  2 
Mediastinum,  297 
MeduUa  (of  brain),  252 

of  bone  (marrow),  11 

fatty  sheath  of  nerve  fiber,  229 
Medullary  canal,  11 
Medullated  fibers,  229,  230 
Membranes  of  body,  5 

of  brain,  254 

of  spinal  cord,  232 
Menopause  (climacteric),  288 
Menstruation,  287 
Mesentery,  137,  300 
Metabolism,  6 
Metacarpus,  54 
Metatarsus,  63 
Metastasis,  201 
Micturition,  214 
Milk,  220 
Mons  veneris,  289 
Motions  of  eyeball,  281 
Mouth  (oral  cavity),  121 
Movable  joint,  description  of,  14 
Mucous  membrane,  5 
Muscles,  action  of,  113,  116 

of  abdomen,  89 

of  back,  80 

of  breast,  96 

of  face,  84 

of  head  and  neck,  82 

of  lower  extremity,  102 

of  mastication,  84 

of  pelvis,  102,  104 

of  upper  extremity,  94 

ribbon,  86 

structure  of,  79,  112 

tension  of,  113 
Muscle  band  of  His,  160 

tissue,  78 
Myocardium,  157, 

Nails,  216 
Nares,  204 
Nasopharynx,  125 
Necrosis  (of  bone),  10 
Nerve  centers,  231 

cylinder,  229 

supply  to  joints,  69 

to  muscle  groups,  118,  259 

tissue,  230 
Nerves,  cervical,  236 

coccygeal,  245 

cranial,  255 

lumbar,  242 

motor,    231 

sacral,  243 

sensory,  231 

spinal,  233,  235 

thoracic,  242 


INDEX 


335 


Neural  cavity.  49 
Neurilemma,  230 
Neuron,  229 
Nose,  202 
Notes,  blood,  153 

blood-vessels,  1 56,  157,  160,  173,  175, 

176,  181,  182,  190 
bones,  20,  50,  52,  55,  61, 63,  66,  67,  72 
digestive  organs,   123,  133,  137,  139, 

146 
lymph  system,  197,  200 
muscles,  77,   78,  82,  91,  96,  97,  98, 
100,  102,  106,  108,  109,110,111 
nerve  system,  229,  233,  264,  274 
pelvic  organs,  288,  290 
respiratory  organs,  206 
skin,  216,  217 
special  senses,  279,  282 
Notes  clinical,  blood-vessels,  164, 173, 175 
bones,  22,  24,  30,  :i2,  34,  39,  51 
digestive    organs,    123,   129,    134, 

i35>  136,  144,  146,  147 

kidney,  213  (two) 

lymph  system,  196  (two),  201 

muscles,  82,  88,  115,  116 

nerve  system,  253,  255,  258 

pelvic  organs,  284,  286, 

regional,  295 

respiratory,  207 

skin,  215,  218 

special  senses,  278,  281  (two) 

spleen,  221 
Notes  obstetric,  28,  46 
Notes  practical  and  special,  blood-vessels, 
166,  178 

bones,  53,  61,  68,  73 

muscles,  76,  84,  90,  92,  100,   103, 
104,  no,  114 

nerve  system,  230,  241,  245,  251 

regional,  293,  310 
Notes  surgical,  bones,  24,  59,  67,  70,  72, 

73 
muscles,  77 
abscess,  93,  220 
Nucleus  and  nucleolus,  2 
caudate,  251 
lentiform,  251 
Nutrient  artery,  10 

Obturator  membrane,  46 

Olfactory  region,  271 

Omentum,  137,  300 

Opsonic  index,  155 

Optic  commissure  (chiasm),  256 

disc,  278 

nerve,  256,  277 

thalamus,  251 
Orbit,  29 

Organ  and  organic  substance,  6,  8 
Origin  of  blood  cells,  73 

of  muscles,  79 
Os  coxa;  or  hip  bone,  44 
Osmosis,  193 


Osseous  tissue,  3,  8 
Ossicles,  275 
Ossification,  11 
Ostium  venosum,  160 
Ovary  and  ovum,  287 
Ovulation,  287 

Palate,  hard,  22 

soft,  121 
Palatine  arches,  123 
Palm,  or  metacarpus,  54 
Pancreas,  137,  221 
Papilla,  hair,  217 

of  skin,  214 

tongue,  122 
Parathyroids,  223 
Patella,  63 

Peduncles  of  brain,  253 
Pelvic  floor,  103 

girdle,  47 

organs,  283 
Pelvis,  47 
Pepsin,  128,  146 
Peptones,  146 
Pericardium,  164 
Perichondrium,  4 
Perineal  arteries,  180 
Perineum,  290 
Perineurium,  231 
Periosteum,  10 
Peristalsis,  137 
Peritoneum,  299 
Perivascular  spaces,  194 
Perspiration,  216 
Peyer's  patches,  134 
Phagocytes,  154 
Phalanges,  55 
Pharynx,  124,  203 
Physiology  of  blood,  192 

of  bone,  73 

of  brain,  260 

of  cord,  245 

of  digestive  organs,  144 

of  kidneys,  213 

of  lymph  system,  201 

of  muscle,  112 

of  nerves,  231,  248 

of  nerve  system,  267 

of  ovary,  287 

of  respiratory  organs,  207 

of  skin,  217 

of  sympathetic  nerves,  264 

of  uterus,  286 
Pia  mater  of  brain,  254 

of  cord,  232 
Pillars  of  fauces,  123 
Pituitary  body  (hypophysis),  224 
Placenta,  192 
Plasma,  154 
Pleura,  206 
Plexus,  cardiac,  264 

celiac,  264 

cervical  236 


Z2,^ 


INDEX 


Plexus,  brachial,  237 

hypogastric,  264 

lumbar,  242 

pulmonary,  264 

sacral,  243 
Pons  varolii,  253 
Popliteal  plane,  60 

space,  106,  107 
Porta  of  liver,  139 
Portal  vein,  189 
Pouch  of  Douglas,  290 
Process  (def.),  10 

acromion,  51 

alveolar,  22 

articular,  35 

coracoid,  51 

coronoid,  53 

frontal,  21 

mastoid,  18 

odontoid,  36 

olecranon,  53 

palate,  21 

pterygoid,  20 

spinous,  35 

styloid,  18,  26 
of  fibula,  61 
of  radius,  53 
of  ulna,  53 

transverse,  35 

unciform,  54 

zygomatic,  18,  22 
Promontory,  38 
Pronation,  58,  59 
Protoplasm,  2 
Ptyalin,  145 
Pubic  arch,  45 

symphysis,  46 
Pudendum,  289 
Pulse,  162 
Pylorus,  128 

Pyramids  and  tracts   (medulla),  252 
decussation  of,  252 


Rachitis,  72 

Receptaculum  chyli,  197 
Rectum,  136 
Reference  tables,  311 
Reflex  action,  246 
Reflex,  abdominal,  247 

patellar,  247 

plantar,  247 

skin,  247 
Rennin,  128,  146 
Respiration,  202 

air  in,  207 

rate  of,  209 
Resume,  alimentary  tract,  137 

course  of  blood  in  heart,  165 

lower  extremity,  68 

upper  extremity,  55 
Retina,  256,  277 
Ribs,  40 


Sacrum,  37 
Saddle  joint,  58 
Saliva,  I24 

Sartorius  or  "tailor  muscle,"  105 
Scalp,  292 

Scarpa's  triangle,  301 
Schneiderian  membrane,  30 
Sciatic  nerves,  243 
Sciatic  notches,  45 
Sclera,  276 

Scrobiculus  cordis,  297 
Scrotum,  290 
Secreting  organs,  6,  225 
Secretions,  6,  225 
Semilunar  notch,  53 
Sensory  impressions,  232 
Septum,  30 
Serous  membrane,  5 
Sheath  of  rectus,  91 
Shoulder  girdle,  50 
Sigmoid  groove,  18,  255 
Sight,  276 
Sinus,  ethmoid,  19 
frontal,  17 
of  kidney,  211 
maxillary,  21 
sphenoid,  20 
transverse  (lateral),  184 
Sinusitis,  30 
Skeleton,  12,  13 
Skin,  214 

Skull,  as  a  whole,  25 
at  birth,  28 

at  different  ages,  70,  71 
bones  of,  16 
completion  of,  71 
points  of  interest,  25 
Smell,  271 
Special  senses,  270 
Speech,  282 
Spermatic  cord,  291 
Sphincter,  anal,  136 
cardiac,  127 
ileo-colic,  134 
pupillary,  277 
pyloric,  128 
vesical,  283 
Spina  bifida,  72 
Spinal  canal,  39 
column,  39 
cord,  231 
Spine  (def.),  10 

intercondyloid,  60 
of  ilium,  45 
of  ischium,  45 
of  pubes,  45 
of  scapula,  51 
Splanchnic  nerves,  264 
Spleen,  lien,  221 
Spongy  or  cancellous  tissue,  9 
Sternum,  43 
Stomach  (gaster),  127 
Straits  of  pelvis,  48 


INDEX 


337 


Supination,  58,  59 

Summary,  cerebro-spinal  nerves,  259 

functions  of  cranial  nerves,  261 
of  skin,  218 
of  spinal  cord,  248 

nerve  system,  267 

respiration,  209 

return  of  lymph,  201 

return  of  venous  blood,  189 

spinal  nerves,  245,  248 
Superciliary  arch,  17 
Supraorbital  margin,  16 

notch  (or  foramen),  17 
Surgical  neck  of  humerus,  52 
Sutures,  20 

Sympathetic  (autonomic)  nerves,  262 
Symphysis  pubis,  45 

sacro-iliac,  46 
Synovial  membrane,  5 
System  (def.),  6 

Tactile  cells,  271 

Tables  of  skull,  25  /» 

Tarsus,  61 

Taste,  272 

Teeth,  31 

eruption  of,  dentition,  32 
Temperature  of  body,  227 
Tendinous  cords,  160 
Tendon   of   Achilles   or   tendo   calcaneus, 

107,  III 
Tendons   79 
Tentorium  cerebelli,  255 
Terminal  filament,  231,  235 
Testes,  291 

Thenar  eminences,  102 
Thorax,  bones  of,  40,  43 
Thymus  body,  223 
Thyroid  (thyreoid)  body,  222 
Tissues,  3 
Tissue  spaces,  194 
Tongue,  121 
Tonsil,  123 

lingual,  123 

palatine,  123 

phar}'ngeal,  125 
Touch,  271 
Trachea,  204 
Triangles  of  neck,  294 
Trigone,  biadrier,  283 

femoral,  301 
Trochanters,  59 
Trochlea,  52 
Trophic  centers,  247 
Trunk,  13,  40 
Tuber  ischii  (tuberosity),  45 


Tubercles  of  humerus,  52 
Tuberosity  of  calcaneus,  62 
Tympanum,  273 

Umbilical  artery,  181 

cord,  192 

vein,  189,  192 
Urea,  149,  213 
Ureter,  212,  283 
Urethra,  284 
Urethral  caruncle,  283 
Urination  (micturition),  214 
Urine,  213 

Uterine  tubes  (Fallopian),  286 
Uterus,  285 
Uvula,  121 

Vagina,  288 

Vaginal  synovial  membranes,  100 
Valve,  Eustachian,  of  heart,  158,  190 
Valve,  Houston's,  136 

ileo-cecal,  134 
Valves  of  heart,  160 

of  veins,  157 
Vasa  vasorum,  157 
Vaso  motor  nerves,  266 
Veins,  structure,  157 
Velum  palati,  121 
Vena  cava  inferior,  187 

superior,  186 
Ventral  cavity,  48 
Ventricles  of  brain,  253 

of  heart,  159 
Vermis  (of  cerebellum),  252 
Vertebrae,  35,  36,  37 
Vertebral  aponeurosis,  So 
Vertex  of  skull,  2  5 
Vestibule  (ear),  274 

(pudendum),  289 
Villi,  131,  148 
Vitreous  body,  278 

layer  (cranial  bones),  25 
Viscera,  abdominal,  299 

thoracic,  297 
Visceral  cavity,  49 
"Vital  knot"  (noeud  vital),  261 
Vocal  bands  and  voice,  281 
Vola,  palm,  68 

Wharton's  jelly,  192 

Xyphoid  appendix,  40 

Y-ligament,  65 

Zygoma,  18 


rate  oi,  . 

Resume,  aliiriv 

course  of  blc^ 
lower  extremity, 
upper  extremity,  ^^ 

Retina,  256,  277 

Ribs,  40 


DUE  DATE 


apT 

I  1  1993 

40V  1  1  ^^ 

OJ 

201-6503 

Printed 
in  USA 

COLUMBIA  UNIVERSITY  LIBRARIES  Ihsl.stx) 

QM  28  B88  1912  C.I 

Text-  hnnl   nf  Jir-^f|-||-|^Y  and 


Bund}/ 

Text-book  of  anatomy  and 
physiology  for  nurses. 


QM28 

B88 

1912 


